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Point-to-Point Tunneling Protocol

The Point-to-Point Tunneling Protocol (PPTP) is an obsolete method for implementing virtual private networks. PPTP has many well known security issues.

PPTP uses a TCP control channel and a Generic Routing Encapsulation tunnel to encapsulate PPP packets. Many modern VPNs use various forms of UDP for this same functionality.

The PPTP specification does not describe encryption or authentication features and relies on the Point-to-Point Protocol being tunneled to implement any and all security functionalities.

The PPTP implementation that ships with the Microsoft Windows product families implements various levels of authentication and encryption natively as standard features of the Windows PPTP stack. The intended use of this protocol is to provide security levels and remote access levels comparable with typical VPN products.

History
A specification for PPTP was published in July 1999 as RFC 2637 and was developed by a vendor consortium formed by Microsoft, Ascend Communications (today part of Nokia), 3Com, and others.

PPTP has not been proposed nor ratified as a standard by the Internet Engineering Task Force.

Description
A PPTP tunnel is instantiated by communication to the peer on TCP port 1723. This TCP connection is then used to initiate and manage a GRE tunnel to the same peer. The PPTP GRE packet format is non standard, including a new acknowledgement number field replacing the typical routing field in the GRE header. However, as in a normal GRE connection, those modified GRE packets are directly encapsulated into IP packets, and seen as IP protocol number 47. The GRE tunnel is used to carry encapsulated PPP packets, allowing the tunnelling of any protocols that can be carried within PPP, including IP, NetBEUI and IPX.

In the Microsoft implementation, the tunneled PPP traffic can be authenticated with PAP, CHAP, MS-CHAP v1/v2.

Security
PPTP has been the subject of many security analyses and serious security vulnerabilities have been found in the protocol. The known vulnerabilities relate to the underlying PPP authentication protocols used, the design of the MPPE protocol as well as the integration between MPPE and PPP authentication for session key establishment.

A summary of these vulnerabilities is below:

 * MS-CHAP-v1 is fundamentally insecure. Tools exist to trivially extract the NT Password hashes from a captured MSCHAP-v1 exchange.
 * When using MS-CHAP-v1, MPPE uses the same RC4 session key for encryption in both directions of the communication flow. This can be cryptanalysed with standard methods by XORing the streams from each direction together.
 * MS-CHAP-v2 is vulnerable to dictionary attacks on the captured challenge response packets. Tools exist to perform this process rapidly.
 * In 2012, it was demonstrated that the complexity of a brute-force attack on a MS-CHAP-v2 key is equivalent to a brute-force attack on a single DES key. An online service was also demonstrated which is capable of decrypting a MS-CHAP-v2 MD4 passphrase in 23 hours.
 * MPPE uses the RC4 stream cipher for encryption. There is no method for authentication of the ciphertext stream and therefore the ciphertext is vulnerable to a bit-flipping attack. An attacker could modify the stream in transit and adjust single bits to change the output stream without possibility of detection. These bit flips may be detected by the protocols themselves through checksums or other means.

EAP-TLS is seen as the superior authentication choice for PPTP; however, it requires implementation of a public-key infrastructure for both client and server certificates. As such, it may not be a viable authentication option for some remote access installations. Most networks that use PPTP have to apply additional security measures or be deemed completely inappropriate for the modern internet environment. At the same time, doing so means negating the aforementioned benefits of the protocol to some point.

title: Point-to-Point Tunneling Protocol


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CS

CS, C-S, C.S., Cs, cs, or cs. may refer to:

Job titles

 * Chief Secretary (Hong Kong)
 * Chief superintendent, a rank in the British and several other police forces
 * Company secretary, a senior position in a private sector company or public sector organisation
 * Culinary Specialist, a US Navy occupational rating

Language

 * Czech language (ISO 639-1 language code)
 * Hungarian cs, a digraph in the Hungarian alphabet

Organizations

 * Christian Social Party (Austria), a major conservative political party in the Cisleithania, part of Austria-Hungary, and in the First Republic of Austria
 * Citizens (Spanish political party), a post-nationalist political party in Spain
 * Congregation of the Missionaries of St. Charles, a Catholic religious congregation, also called Scalabrinians
 * Confederate States of America, an unrecognized confederation of secessionist North American slave states existing from 1861 to 1865

Companies

 * Colorado & Southern Railway, a railroad company in the western United States
 * Comlux Aruba NV (IATA airline code: CS)
 * Connecting Stockholm, future train operator in Sweden
 * Copenhagen Suborbitals, a Danish non-profit rocket group working on the HEAT1X-TYCHO BRAHE rocket
 * CouchSurfing, a hospitality service
 * Credit Suisse, a Swiss financial services company
 * Comp-Sultants, a defunct microcomputer company
 * CS Wind, a South Korea-based manufacturer of wind turbine towers

Places

 * Cannon Street station, London, UK, abbreviated CS in UK railway slang
 * Czechoslovakia (former ISO 3166-1 country code)
 * Serbia and Montenegro (former ISO 3166-1 country code)

Biology and medicine

 * Cardiogenic shock, a medical emergency where heart fails to pump properly to push blood forward.
 * Caesarean section, a surgical procedure to deliver one or more babies, or, rarely, to remove a dead fetus
 * Cockayne syndrome, a rare autosomal recessive, congenital disorder
 * Conditioned stimulus, in the psychological procedure of classical conditioning
 * Corticosteroids, a class of hormones produced in vertebrates, and their synthetic analogues
 * Cowden syndrome, a rare autosomal dominant inherited disorder
 * (-)-camphene synthase, an enzyme
 * CS (gene), which encodes the enzyme citrate synthase

Chemistry

 * Caesium or Cesium, symbol Cs, a chemical symbol
 * Carbon monosulfide, chemical formula CS

Computing

 * Computer science, the scientific and practical approach to computation and its applications
 * CS register, or code segment register, in X86 computer architecture
 * Cable select, an ATA device setting for automatic master/slave configuration
 * Checkstyle, a Java static code analysis tool
 * Chip select, a control line in digital electronics
 * ChanServ, an IRC network service
 * Construction Set, a program for creating or editing PC games (i.e. The Elder Scrolls Construction Set)
 * Adobe Creative Suite, a design and development software suite by Adobe Systems
 * C#, a general-purpose, multi-paradigm programming language.

Mathematics

 * cs (elliptic function), one of Jacobi's elliptic functions

Other uses in science and technology

 * Carbon steel
 * Cirrostratus cloud
 * Citizen science
 * Compressed sensing, a signal processing technique for reconstructing a signal using underdetermined linear systems
 * Control segment, part of the structure of the Global Positioning System
 * Counter-scanning, a scanning method that allows correcting raster distortions
 * cS, another form for cSt, for centistokes, a unit of viscosity
 * CS gas, a riot control agent

Other uses

 * Controlled substance, generally a drug or chemical whose manufacture, possession, or use is regulated by a government
 * Cable Ship, in civilian ship names
 * Calgary Stampede, a rodeo
 * Caught stealing, a statistic in baseball
 * Chhatrapati Shivaji, c. 1627/1630 – 1680), Indian warrior king and member of the Bhonsle Maratha clan
 * Christian Science, a religion
 * Cities: Skylines, 2015 city-building simulation video game
 * Coke Studio (disambiguation), several musical television shows
 * Counter-Strike, a series of video game first released as a 1999 modification for Half-Life
 * Cum Suis (Latin: "and associates"); see List of Latin phrases
 * Customer service, the provision of service to customers before, during and after a purchase and sale
 * Bombardier-Airbus C-Series, small jetliner
 * Ferrari 360 Challenge Stradale
 * A US Navy hull classification symbol: Scout cruiser (CS)
 * Post-nominal letters for the Missionaries of St. Charles Borromeo (Scalabrinians), a Catholic religious congregation

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: CS


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George Washington Bridge

The George Washington Bridge is a double-decked suspension bridge spanning the Hudson River, connecting Fort Lee in Bergen County, New Jersey, with the Washington Heights neighborhood of Manhattan in New York City. It is named after Founding Father George Washington, the first president of the United States. The George Washington Bridge is the world's busiest motor vehicle bridge, carrying a traffic volume of over 104million vehicles, and is the world's only suspension bridge with 14 vehicular lanes.

The bridge is owned by the Port Authority of New York and New Jersey, a bi-state government agency that operates infrastructure in the Port of New York and New Jersey. The George Washington Bridge is also informally known as the GW Bridge, the GWB, the GW, or the George, and was known as the Fort Lee Bridge or Hudson River Bridge during construction. The George Washington Bridge measures 4760 ft long, and its main span is 3500 ft long. It was the longest main bridge span in the world from its 1931 opening until the Golden Gate Bridge in San Francisco opened in 1937.

The George Washington Bridge is an important travel corridor within the New York metropolitan area. It has an upper level that carries four lanes in each direction and a lower level with three lanes in each direction, for a total of 14 lanes of travel. The speed limit on the bridge is 45 mph. The bridge's upper level also carries pedestrian and bicycle traffic. Interstate 95 (I-95) and U.S. Route 1/9 (US 1/9, composed of US 1 and US 9) cross the river via the bridge. U.S. Route 46 (US 46), which lies entirely within New Jersey, terminates halfway across the bridge at the state border with New York. At its eastern terminus in New York City, the bridge continues onto the Trans-Manhattan Expressway (part of I-95, connecting to the Cross Bronx Expressway).

The idea of a bridge across the Hudson River was first proposed in 1906, but it was not until 1925 that the state legislatures of New York and New Jersey voted to allow for the planning and construction of such a bridge. Construction on the George Washington Bridge started in September 1927; the bridge was ceremonially dedicated on October 24, 1931, and opened to traffic the next day. The opening of the George Washington Bridge contributed to the development of Bergen County, New Jersey, in which Fort Lee is located. The upper deck was widened from six to eight lanes in 1946. The six-lane lower deck was constructed beneath the existing span from 1959 to 1962 because of increasing traffic.

Description
The George Washington Bridge was designed by chief civil engineer Othmar Ammann,  design engineer Allston Dana, and assistant chief engineer Edward W. Stearns, with Cass Gilbert as consulting architect. It connects Fort Lee in Bergen County, New Jersey, with Washington Heights in Manhattan, New York. The bridge's construction required 113000 ST of fabricated steel; 28000 ST of wire, stretching 106000 mi; and 20000 ST of masonry.

Decks
The bridge carries 14 lanes of traffic, seven in each direction. As such, the George Washington Bridge contains more vehicular lanes than any other suspension bridge and is the world's busiest vehicular bridge. The fourteen lanes of the bridge are split unevenly across two levels: the upper level contains eight lanes while the lower level contains six lanes. The upper level opened on October 25, 1931, and is 90 ft wide. The upper level originally had six lanes, though two more lanes were added in 1946. Although the lower level was part of the original plans for the bridge, it did not open until August 29, 1962. The upper level has a vertical clearance of 14 ft, and all trucks and other oversize vehicles must use the upper level. Trucks are banned from the lower level, which has a clearance of 13.6 ft. All lanes on both levels are 8 ft wide. Vehicles carrying hazardous materials (HAZMATs) are prohibited on the lower level due to its enclosed nature. HAZMAT-carrying vehicles may use the upper level, provided that they conform to strict guidelines as outlined in the Port Authority's "Red Book". There are two sidewalks on the upper span of the bridge, one on each side. The northern sidewalk was largely closed after the September 11 attacks; it reopened in 2017 while a temporary suicide prevention fence was installed on the southern sidewalk, in preparation for the installation of permanent fences on both sidewalks. Prior to 2023, pedestrians had to traverse a total of 171 steps while using the northern sidewalk. As part of a renovation, the steps were replaced by a ramp, and two viewing platforms were added.

The George Washington Bridge has a total length of 4760 ft, whilet its main span is 3500 ft long. Accounting for the height of the lower deck, the bridge stretches 212 ft above mean high water at its center, and 195 ft above mean high water under the New York anchorage. The bridge's main span was the longest main bridge span in the world at the time of its opening in 1931, and was nearly double the 1850 ft of the previous recordholder, the Ambassador Bridge in Detroit. It held this title until the opening of the Golden Gate Bridge in 1937. Prior to the bridge's construction, engineers had believed that a suspension span's length was a large indicator of a suspension bridge's economic feasibility, but the bridge's completion proved that longer suspension bridges were both physically and economically feasible.

The George Washington Bridge's total width is 119 ft. When the upper deck was built, it was only 12 ft thick without any stiffening trusses on the sides, resulting in a deck weighing 1100 lb/ft2 and a length-to-thickness ratio of about 350 to 1. At the time of the George Washington Bridge's opening, most long suspension spans had stiffening trusses on their sides, and spans generally had a length-to-thickness ratio of 60 to 1, which translated to a weight of 13000 to 14000 lb/ft2 and a thickness equivalent to an 11-story building. During the planning process, Ammann designed the deck around the "deflection theory", an as-yet-unconfirmed assumption that a longer suspension deck did not need to be as stiff in proportion to its length, because the weight of the longer deck itself would provide a counterweight against the deck's movement. This had been tested by Leon Moisseiff when he designed the Manhattan Bridge in 1909, though it was less than half the length of the George Washington Bridge. Stiffening trusses were ultimately excluded from the George Washington Bridge's design to save money; instead, a system of plate girders was installed under the upper deck. This provided the stiffening that was necessary for the bridge deck, and it was replicated on the lower deck during its construction. The plate-girders underneath each deck, combined with an open-truss design on the bridge's side that connected the decks with each other, resulted in an even stiffer span that was able to resist torsional forces.

Cables

Four 3 ft-diameter main cables support the bridge deck. Each main cable contained 61 strands, with each strand made of 434 individual wires, for a total of 26,474 wires per main cable, and 105,986 in all. The cables are covered by a sheath of weather-resistant steel. The upper bridge deck is held by vertical suspender wires attached directly to the main cables by saddle connections; the lower deck is supported by girders attached to the upper.

The main cables are anchored in concrete on both sides of the bridge, in a purpose-built anchorage on the New York side and bored and set directly into the cliffs of the Palisades on the New Jersey side. Originally, the end of each cable was supposed to receive one of several ornamental designs, such as a wing, fin, tire, or statue; cost-savings after the start of the Great Depression in 1929 preempted the flourishes.

Suspension towers
The suspension towers on each side of the river are each 604 ft tall. They are composed of sections weighing between 37 and 40 ST and contain a combined 475,000 rivets. Each bridge has two archways, one above and one below the decks. The George Washington Bridge is classified as a fracture critical bridge, making it vulnerable to collapse if parts of the towers were to fail, although the towers are located offshore.

The original design called for the towers to be encased in concrete and granite in a Revival style, similar to the Brooklyn Bridge. Additional scrutiny of the proposed bridge's engineering found that the steel alone could support the towers, with only a decorative stone facade being retained in the plan. Elevators to carry sightseers to restaurants and observatory proposed decks at the top of each tower were also all pared from the design. Ultimately, even stone facades were postponed in 1929 during the Great Depression due to rising material costs. Even though the steel towers had been left that way for cost reasons, some aesthetic critiques of the bare steel towers were favorable. Several groups, such as the American Institute of Steel Construction, believed that covering the steel framework with masonry would be both misleading and "fundamentally ugly".

While the exposed steel towers' design was negatively received by a few critics such as Raymond Hood and William A. Boring, the public reception at the bridge's opening was generally positive. The Swiss-French architect Le Corbusier wrote of the towers: "The structure is so pure, so resolute, so regular that here, finally, steel architecture seems to laugh." Milton MacKaye wrote in The New Yorker that the George Washington Bridge had established Ammann as "one of the immortals of bridge engineering and design, a genius." Ammann never incorporated masonry towers in his bridge plans again. He wrote that the "sturdy appearance and well-balanced distribution of steel in the columns and bracing" gave the bridge's towers "a good appearance, a neat appearance". Over time, the exposed steel towers, with their distinctive criss-crossed bracing, became one of the George Washington Bridge's most identifiable characteristics.

American flag

Since 1947 or 1948, the bridge has flown the world's largest free-flying American flag on special occasions. Hung inside the arch of the New Jersey tower, it measures 90 ft long, 60 ft wide, and 450 lbs. Until 1976, the flag was taken out of a garage in New Jersey and manually erected on national holidays. During the United States' bicentennial, a mechanical hoisting system was installed, and the flag was stored along the bridge's girders when not in use. When weather allows, it is hoisted on Martin Luther King Jr. Day, Presidents Day, Memorial Day, Flag Day, Independence Day, Labor Day, Columbus Day, and Veterans Day. Since 2006, the flag is also flown on September 11 of each year, honoring those lost in the September 11 attacks. On events where the flag is flown, the tower lights are lit from dusk until 11:59 p.m.

History
The bridge sits near the sites of Fort Washington (in New York) and Fort Lee (in New Jersey), which were fortified positions used by General George Washington and his American forces as they attempted to deter the occupation of New York City in 1776 during the American Revolutionary War. Unsuccessful, Washington evacuated Manhattan by ferrying his army between the two forts.

By the end of the 19th century there were more than 200 separate municipalities along the lower Hudson River and the New York Bay, with no unified agency to control commerce or transport in the area and no fixed crossing. The first was proposed in 1888 by civil engineer Gustav Lindenthal, who later became New York City's bridge commissioner. The Hudson and Manhattan Railroad and the Pennsylvania Railroad opened three pairs of tubes under the lower Hudson in the 1900s. The first vehicular crossing across the lower Hudson River, the Holland Tunnel, was opened in 1927, connecting Lower Manhattan with Jersey City.

Planning

A vehicular bridge across the Hudson River was being considered as early as 1906, during the planning for the Holland Tunnel. Three possible locations for a suspension bridge were considered in the vicinity of 57th, 110th, and 179th Streets in Manhattan, with others rejected on the grounds of aesthetics, geography, or traffic flows. In 1920, English architect Alfred C. Bossom proposed a double-decker bridge with room for vehicular and railroad traffic near 57th Street in Midtown Manhattan. The same year, Othmar Ammann and Gustav Lindenthal proposed a vehicular and railroad bridge to 57th Street in Manhattan, topped by an office building on the Manhattan end that would have been the world's tallest. Lindenthal's plan failed because it did not receive permits from the United States Army Corps of Engineers or approval from the city, and because Midtown Manhattan real estate developers and planners opposed the plan. Ammann unsuccessfully attempted to convince Lindenthal to build his bridge elsewhere, without a tower atop the bridge's terminus. In January 1924, the New York State Chamber of Commerce voted against the 57th Street location in favor of another upstream. Despite this, Lindenthal proposed that a bridge be built there, and carry 16 railroad tracks and 12 lanes of automotive traffic.

Meanwhile, Ammann became chief engineer of the Port of New York Authority (now the Port Authority of New York and New Jersey), which was created in 1921 to oversee commerce and transport along the lower Hudson River and New York Bay. He had disassociated himself from Lindenthal's proposal by 1923, conducting his own studies on the feasibility of a bridge from 178th Street in Fort Washington, Manhattan, to Fort Lee in New Jersey. Ammann's advocacy for the Fort Washington–Fort Lee bridge gained support from both New Jersey governor George Silzer and New York governor Alfred E. Smith by mid-1923. In May 1924, Colonel Frederick Stuart Greene, the New York Superintendent of Public Works, announced a plan to construct a suspension bridge between Fort Lee and Fort Washington. At that location, both sides were surrounded by steep cliffs (The Palisades on the New Jersey side, and Washington Heights on the New York side). Thus, it was possible to build the bridge without either impeding maritime traffic or requiring lengthy approach ramps from ground level.

A New Jersey state assemblyman introduced a bill for the Hudson River bridge that December. This bill was passed in the New Jersey Assembly in February 1925. After an initial rejection by Silzer, the Assembly made modifications before passing the bill again in March, after which Silzer signed the bill. Around the same time, the New York state legislature was also considering a similar bill. A dispute developed between New York civic groups, who supported the construction of the Hudson River Bridge; and the Parks Conservation Association, who believed that the bridge towers would degrade the quality of Fort Washington Park directly underneath the proposed bridge's deck. In late March 1925, the chairman of the Parks Conservation Association noted that the proposed New York state legislation would provide for the actual construction of the bridge, rather than just the planning. Ultimately, the Hudson River bridge bill was passed in the New York state legislature, and Smith approved the bill that April.

In March 1925, Silzer asked Ammann to devise preliminary plans for the Hudson River bridge. Ammann found that the width of the Hudson River decreased by more than 1000 ft when it passed between Fort Lee and Fort Washington. The ledges of Fort Lee and Fort Washington were respectively 300 and 200 ft above mean water level at this point, which was not only ideal geography for a suspension bridge, but also allowed the bridge to be high enough to give sufficient clearance for maritime traffic. However, the differing heights meant that a large cut had to be made through the Fort Lee ledge so that the bridge approach could be built there. The same month, the New Jersey legislature asked for funds for test bores to determine if the geological strata would support the bridge. In response to continuing concerns from park preservationists, Ammann stated that placing the New York suspension tower anywhere else would make the bridge look asymmetrical, which he believed was a worse outcome than placing the tower within the park.

The states conducted a study in mid-1925, which found that the Hudson River bridge would be able to pay for itself in twenty-five years if a 50-cent toll were to be placed on every vehicle. After funding was secured, surveyors began examining feasible sites for the future bridge's approaches in August 1925. By law, the New York end of the Hudson River Bridge could only be constructed between 178th and 185th Streets, and the New Jersey end had to be built directly across the river. Geologists made 300 ft test bores on the New Jersey side to determine if the site was feasible for laying foundations for the bridge. Othmar Ammann was hired as the bridge's chief engineer. In Ammann's original plans for the bridge, which had been published in March 1925, he had envisioned that the bridge would contain two sidewalks; a roadway that could carry up to 8,000 vehicles per hour; and space for four railroad tracks, in case the two North River railroad tunnels downstream exceeded their train capacity. Cass Gilbert was hired in January 1926 to design architectural elements for the Hudson River bridge, including the suspension towers. The bridge design had yet to be finalized, and its cost could not even be estimated at that point due to the complexity of factors.

Gilbert released preliminary sketches of the Hudson River bridge that March; by then, the architect had decided that the span would be a suspension bridge. The sketch accompanied a feasibility report that Ammann and other engineers presented to the Port of New York Authority, which was to operate the bridge. The central span was to be 3500 ft long, longer than any other suspension bridge in existence at the time, and 200 feet above mean high water. The bridge would initially carry four lanes of vehicular traffic and sidewalk lanes; the plans called for three additional phases of expansion, culminating in an eight-lane bridge deck with four rapid-transit tracks underneath. The span would be supported by two towers, each 650 ft tall. There would also be space to build a second deck in the future below the main deck. Ammann's team also found that the most feasible location for the bridge was at 179th Street in Manhattan (as opposed to 181st or 175th Streets). This was both because the 179th Street location was more aesthetically appealing than the other two locations, and because a 179th Street bridge would be cheaper and shorter in length than a bridge at either of the other streets. At this point in the planning process, the Hudson River bridge's estimated cost was $40million or $50million. Because of the proposed bridge's length, engineers also had to test the strength of materials, including suspension cables, that were to be used in the span. Ammann's research department constructed scale models of various designs for the bridge and tested them in wind tunnels.

By late 1926, one engineer predicted that construction on the Hudson River bridge would start the following summer. In December 1926, the final plans for the bridge were approved by the public and by the War Department. The Port Authority planned to sell off $50million worth of bonds to pay for the bridge, and the initial $20million bond issue was sold that December. Further issues arose when the New Jersey Assembly passed a bill in March 1927, which increased the New Jersey governor's power to veto Port Authority contracts. Smith, the New York governor, and Silzer, the now-former New Jersey governor who had been appointed Port Authority chairman, both objected to the bill since the Port Authority had been intended as a bi-state venture. Afterward, the then-current New Jersey governor A. Harry Moore worked with legislators to revise the legislation. The revised law was ultimately not a significant deviation from the Port Authority's practice at the time, wherein the Port Authority was already submitting its contracts to New Jersey government for review.

Construction
The George Washington Bridge's construction employed three teams of workers: one each for the New Jersey tower, the New York tower, and the deck. The construction process was relatively safe, although twelve or thirteen workers died during its construction. Of these, three were killed when the foundation for the New Jersey tower flooded; a fourth worker was killed by a blast at the New Jersey anchorage; and the others died because of their own carelessness, according to Port Authority records.

First contracts
In April 1927, the Port Authority opened the first bids for the construction of the Hudson River bridge. It was specifically seeking bids for the construction of the New Jersey suspension tower's foundation. The Manhattan suspension anchorage's location was still undecided at this time. A bid for the New Jersey tower was awarded later that month. In May, the Port Authority opened more bids for the construction of the bridge's approaches and anchorage on the New Jersey side. Dredging operations on the Hudson River, which would allow large ships to pass underneath the bridge, also started that May. By late August, the Port Authority had started condemning plots of land for the bridge's approaches.

Montgomery B. Case, the bridge’s chief construction engineer, began construction on the Hudson River bridge on September 21, 1927, with groundbreaking ceremonies held at the sites of both future suspension towers. Each tower was to have a base with a perimeter measuring 89 by, and descending 80 feet into the riverbed. The riverbed around the towers' sites was dredged first, and then steel pilings were placed in the riverbed to create a watertight cofferdam. The cofferdams for the bridge were the largest ever built at the time. In early October of that year, the Port Authority received bids for the construction of the bridge deck. There were two main methods being considered for the span's construction: the cheaper "wire-cable" method and the more expensive "eyebar" method. The wire-cable method, where the vertical suspender wires are attached directly to the main cables and the deck directly, would require a stiffening truss to support the deck. The eyebar method, where the suspender wires are attached to a chain of eyebars (metal bars with holes in them), would be self-supporting. Ultimately, the Port Authority chose the wire-cable design because of costs, and it awarded the contract for constructing the deck to John A. Roebling Sons' Company. The corresponding contract for manufacturing the steel was awarded to the. The first serious accident during the bridge's construction occurred in December 1927, when three men drowned while working in a caisson on the New Jersey side.

Towers and anchorages

Bids for the Manhattan suspension tower were advertised in March 1928. At this point, 64% of the total projected worth of construction contracts had been awarded. The piers that provided foundation for the New Jersey suspension tower and approaches were being constructed. The cliffs on both sides of the river were high enough that only minimal bridge approaches were required on either side. The towers' foundations could reach at most 190 ft below mean low water, where the foundations would hit a layer of solid rock. In May 1928, builders started drilling a 50 ft cut through the Palisades on the New Jersey side so that the Hudson River bridge approach could be built. By June 1928, half of the money earned during the previous year's $20million bond sale had been spent on construction. By that October, nearly all blasting operations had been completed. The suspension tower on the New Jersey side had been constructed to a height of 250 ft, and the tower on the New York side was progressing as well. The suspension towers consisted of 13 segments, each of which were almost 50 feet high.

The New York anchorage required 370000 ST of concrete, being freestanding, while the New Jersey anchorage was blasted into the Palisades. By March 1929, the concrete structure of the New York anchorage had been completed, three months ahead of schedule. The anchorage on the New Jersey side, which had been fully bored, consisted of two holes that had been bored 250 feet into the face of the Palisades. On the New Jersey side, 225,000 yd3 of rock had to be blasted out to make way for the New Jersey approach. The suspension towers were nearly complete at the time of the report; only 100 feet of each tower's height remained to be built. Anchors were being placed in the two holes that were being drilled for the New Jersey anchorage, and this task was also nearing completion.

In April, the Port Authority acquired the last of the properties that were in the path of the bridge's Manhattan approach. Plans for the Manhattan approach were approved by the New York City Board of Estimate around the same time. The approach was to consist of scenic, meandering ramps leading to both Riverside Drive and the Henry Hudson Parkway, which run along the eastern bank of the Hudson River at the bottom of the cliff in Washington Heights. The bridge would also connect to 178th and 179th Streets, at the top of Washington Heights. A third connection would be made to an underground highway running between and parallel to 178th and 179th Streets; this connection would become the 178th–179th Street Tunnels, and would later be replaced by the Trans-Manhattan Expressway. The original plan for the approach to the underground highway stated that the approach would be made using a monumental stone viaduct descending from the span at a 2.2% gradient. The Port Authority started evicting residents in the approach's path in October 1929. The same month, the Port Authority sold the final $30million in bonds to pay for the bridge.

The plans for the Hudson River bridge's Fort Lee approach were also changed in January 1930. Originally, the bridge would have terminated in a traffic circle, a type of intersection design that was being built around New Jersey during the 1920s and 1930s. However, the revised plans called for a grade-separated highway approach that would connect to a traffic "distributing basin" with ramps to nearby highways. The total cost of land acquisition for the bridge approaches on both sides of the Hudson River exceeded $10million.

Cable spinning
After the towers were completed, two temporary catwalks were built between the two suspension towers. Then, workers began laying the bridge's four main cables, a series of thick cables that stretch between the tops of the two towers and carry what would later become the upper deck. The first strand of the first main cable was hoisted between both towers in July 1929, in a ceremony attended by the governors of both states and the mayors of New York City and Fort Lee. The two temporary catwalks allowed workers to spin the wires for the main cables on-site. The wires for the cables were spun by dozens of reels at a dock near the base of the New York anchorage; each reel contained 30 miles of wire at any given time. A total of 105,986 wires were used in the bridge when it was completed.

By February 1930, the bridge was halfway complete; since construction was two months ahead of schedule, the bridge was scheduled to open in early 1932. A team of 350 men was spinning the wires for each of the 36 in main cables, which were 22% complete. In addition, the builders had started ordering steel for the deck. By April, the spinning of the main cables was half complete. The first main cable was completed in late July 1930, and the other three main cables were completed that August, with the laying of the last wire being marked by a ceremony. The spinning of the main cables had taken ten months in total.

After the main cables were laid, workers spun the suspender wires that connected the main cables with the deck. When it was finished, the system of cables would support 90,000 ST of the deck's weight, though the cables would be strong enough to carry 350,000 ST, four times as much weight. The construction of a lower deck for rail usage was postponed, since the start of the Depression meant that there would not be enough railroad traffic to justify the construction of such a deck in the near future.

Nearing completion
An agreement between the Port of New York Authority and the City of New York, dated July 29, 1930, was formed to convey property and property easements granted in relation to the New York Approach to the then Hudson River Bridge. That month, the Port Authority opened the bidding process for contracts to build the Hudson River bridge's approaches on the New York side. These included contracts for the 178th-179th Street Tunnels and the Riverside Drive connection. The tunnel contracts were awarded later that month. In August, the bidding process for the Fort Lee approaches was opened. Bids for the Riverside Drive connection were received the following month.

Prior to and during construction, the bridge was unofficially known as the "Hudson River Bridge" or "Fort Lee Bridge". The Hudson River Bridge Association started seeking suggestions for the bridge's official name in October 1930. Residents of New York and New Jersey were encouraged to send naming choices to the association, which would then forward the suggestions to the Port Authority. According to ballot voting submitted to the Port Authority, the "Hudson River Bridge" name was the most popular choice. The Port Authority preferred the name "George Washington Memorial Bridge", which had been proposed by a board member, and still others championed the name "Palisades Bridge". However, the Port Authority formally adopted the "George Washington" name on January 13, 1931, honoring the general and future president's evacuation of Manhattan at the bridge's location during the Revolutionary War. This was described as potentially confusing, since there was already a "Washington Bridge" connecting 181st Street with the Bronx, directly across Manhattan from the "George Washington Bridge" across the Hudson River. Shortly afterward, the Port Authority Board of Commissioners voted to reconsider the renaming of the Hudson River Bridge, stating that it was open to alternate names. Hundreds of naming choices had been submitted by this time. The most popular naming choices were those of Washington, Christopher Columbus, and Hudson River namesake Henry Hudson. The span was again officially named for George Washington in April 1931. This decision was applauded by then-congressman Fiorello La Guardia, who felt that other options "insulted the memory of our first President and encouraged the Reds".

The system of girders to support the deck was installed throughout 1930, and the last girder was installed in late December 1930. In March 1931, the Port Authority announced that the Hudson River Bridge was set to open later that year, rather than in 1932 as originally planned. At that time, the Port Authority had opened bids for paving the road surface. Later that month, the agency published a report, which stated that the bridge's early opening date was attributable to how quickly and efficiently the various materials had been transported. In June 1931, forty bankers became the first people to cross the bridge.

Work was progressing quickly on the bridge approaches in New Jersey, and the New York City government was considering building another bridge between Manhattan and the Bronx (the Alexander Hamilton Bridge) to connect with the George Washington Bridge. Bids for constructing tollbooths and floodlight towers were opened in July 1931.

1930s to 1960s
The George Washington Bridge was dedicated on October 24, 1931, and the bridge opened to traffic on October 25, 1931, eight months ahead of schedule. The opening ceremony, attended by 30,000 guests, was accompanied by a show from military airplanes, as well as speeches from politicians including Morgan Foster Larson, the governor of New Jersey, and Franklin D. Roosevelt, the governor of New York. The first people to cross the George Washington Bridge were reportedly two elementary school students who roller-skated across the bridge from the New York side. Pedestrians were allowed to walk the length of the George Washington Bridge between 6 p.m. and 11 p.m. The bridge was formally opened to traffic the next day. The Port Authority collected tolls for drivers who used the bridge in either direction; as with the Holland Tunnel, the toll was set at 50 cents for passenger cars, with different toll rates for other vehicle types. Pedestrians paid a toll of 10 cents each, which was lowered to 5 cents in 1934. Within the first 24 hours of the George Washington Bridge's official opening, 56,312 cars used the span, as well as 100,000 pedestrians (including those who had walked across after the ceremony). The Port Authority reported that 33,540 pedestrians crossed the bridge on the first day, of which 20,000 paid a toll to cross.

During the George Washington Bridge's construction, the cost of the bridge was estimated at $75million, and the bridge was expected to carry eight million vehicles and 1.5million pedestrians in its first year. When the George Washington Bridge opened, it was estimated that eight million vehicles would use the bridge in its first year, and that the bridge could ultimately carry 60million vehicles annually after a second deck was added. The bridge's final cost was estimated at $60million. Real-estate speculators believed that the bridge's construction would raise real-estate values in Fort Lee, since the borough's residents would be able to more easily access New York City. During the construction of the George Washington Bridge, speculators spent millions of dollars to buy land around the bridge's New Jersey approach. The bridge was later credited with helping raise land prices and encouraging residential development in formerly agricultural parts of Bergen County. It also spurred the rise of the trucking industry along the United States' East Coast, supplanting much of the freight railroads that used to carry cargo. In the George Washington Bridge's first week of operation, the bridge carried 116,265 vehicles, compared to the Holland Tunnel's 173,010 vehicles, despite the fact that the tunnel had fewer lanes than the bridge did. During that time span, 56,000 pedestrians used the bridge. A week after the bridge opened, the 10-lane tollbooth was expanded to 14 lanes because of heavy weekend traffic volumes. During its first year, the George Washington Bridge saw 5.5million vehicular crossings and nearly 500,000 pedestrian crossings. Traffic counts on the George Washington Bridge grew year after year. By the time of the bridge's tenth anniversary in 1941, the span had been used by 72million vehicles total, including a record 9.1million vehicles in 1940.

On February 22, 1932, George Washington's 200th birthday, the Port Authority planted 70 red oak trees along an approach to the bridge. New Jersey Route 4, which connected directly to the bridge's western end, opened in July 1932. The 178th-179th Street Tunnels, which connected Amsterdam Avenue on the eastern side of Manhattan to the bridge's eastern end on the west side of Manhattan, were supposed to be completed in late 1932. Direct approaches to Riverside Drive and the Hudson River Parkway were completed in 1937, and the tunnels were completed in 1938–1939. A ramp eastward from the bridge and southward to the Harlem River Drive was also completed around this time. The bridge's westbound entrance ramp from Fort Washington Avenue, at the top of the cliff on the Manhattan side, opened in April 1939; another approach in New Jersey had opened by July 1939. The corresponding eastbound exit ramp, as well as the 178th Street Tunnel, opened in June 1940, while the 179th Street Tunnel opened in 1950. In May 1935, a court ruled that the New Jersey and New York governments controlled their respective sides of the bridge.

The bridge was initially lit by 200 lights to provide warning to pilots flying at night. The Port Authority enacted a photography ban during World War II in the 1940s. An aviation obstruction light was installed in 1936 as a memorial to Will Rogers. Additionally, from May 1942 to May 1945, the lights on the bridge were shut off at night as a precautionary measure. After the war ended, the lights were turned back on, but the photography ban was upheld. In August 1946, the bridge's towers were repainted. The underside of the bridge was also repainted in May of the following year.

Originally, the George Washington Bridge's deck consisted of six lanes, with an unpaved center median. In 1946, the median was paved over and two more lanes were created on the upper level, widening it from six lanes to eight lanes. The two center lanes on the upper level served as reversible lanes, which could handle traffic in either direction, depending on witch directo had the greater traffic flow.

In November 1950, workers began to tighten the bridge's suspender ropes after almost 20 years of being in place; the project was completed by 1951. New ramps onto the Henry Hudson Parkway were opened in late 1953, followed by the ramps with the Palisades Interstate Parkway in December 1954. In addition, the barrier system on the bridge was adjusted in mid-1954, and new navigational signs were added to assist motorists. In 1955, the lighting system on the deck was replaced, the old lighting was obsolete and frequently glared.

1960s: Modernization and lower level
Construction of the lower deck, as well as the construction of a new bus terminal and other highway connections near the bridge, were recommended in a 1955 study that suggested improvements to the New York City area's highway system. The lower deck was approved by the U.S. Army Corps of Engineers. A Bergen County leader voted against the construction of the lower level in 1956, temporarily delaying construction plans. The New York City Planning Commission approved the George Washington Bridge improvement in June 1957, and the Port Authority allocated funds to the improvement that July. The $183million project included the construction of the lower deck; the George Washington Bridge Expressway, a 12-lane expressway connecting to the Alexander Hamilton Bridge and the Cross Bronx Expressway (later I-95 and US 9); the George Washington Bridge Bus Station above the expressway; and a series of new ramps to and from the Henry Hudson Parkway. On the New Jersey side, two depressed toll plazas, one in each direction, were to be constructed for lower level traffic. Highway connections were also being built on the New Jersey side, including a direct approach from I-95.

Construction of the approaches started in September 1958. Work on the lower level itself started on June 2, 1959, but work was briefly halted later that year because of a lack of steel. By February 1960, construction was underway on the lower level; the supporting steelwork for the future deck had been completed, and the sections for the lower deck were being installed. The George Washington Bridge's lower deck would comprise 75 steel slabs; each slab weighed 220 tons and measured 108 ft wide by 90 ft feet long, with a thickness of 30 ft. The construction of the slabs proceeded from either side of the bridge. The right-of-way for the George Washington Bridge Expressway had been almost entirely cleared except for the ventilation buildings for the 178th-179th Street Tunnels. During construct The segments of the lower deck had been laid completely by September 1960, at which point workers started pouring the concrete for the deck's roadway, a process that took five weeks. The layer of concrete measured 4 in thick. Finally, the deck was paved over with a 2.5 in layer of asphalt.

New ramps to the George Washington Bridge in New Jersey, including from the newly completed I-95, opened in mid-1962. The lower deck was opened to the public on August 29, 1962. The lower level, nicknamed "Martha" after George's wife Martha Washington, increased the capacity of the bridge by 75 percent, and simultaneously made the George Washington Bridge the world's only 14-lane suspension bridge. In addition to providing extra capacity, the lower level served to stiffen the bridge in high winds; before the lower deck was constructed, the George Washington Bridge was known to swing up to 30 in. The George Washington Bridge Bus Station opened on January 17, 1963 and the Alexander Hamilton Bridge opened on January 15, 1963, thus allowing more traffic to use the George Washington Bridge. In the first year after the lower level's opening, the expanded bridge had carried 44million vehicles. By comparison, 35.86million vehicles had crossed the bridge in an 11-month period between September 1, 1961 and July 31, 1962. In addition, traffic congestion at the George Washington Bridge was reduced after the lower level opened, and the Port Authority repaired the upper level for the first time in the bridge's history.

1970s to 1990s
A fixed median was added to the upper deck in 1970; the concrete barrier was destroyed to allow for such. The next year, I-95 was extended across through New Jersey.

In early 1977, a project to replace the deteriorated deck on the upper level began. The original deck was demolished, and the new deck, which was constructed beforehand, was placed. As part of the project, the eastbound lanes on the upper level were partially closed; the westbound upper-level lanes carried two-way traffic during off-peak hours. The PANYNJ also encouraged traffic to use the lower level. It was completed in late 1978.

The bridge was carrying 82.8million vehicles per year by 1980. The American Society of Civil Engineers named the bridge as a National Historic Civil Engineering Landmark on October 24, 1981, the 50th anniversary of the bridge. The 50th anniversary was also marked with a parade of automobiles. At that point, 1.8billion vehicles had used the bridge throughout its lifetime. The bridge was repaired in 1984, and the bridge's upper deck was resurfaced in 1987. After one a building above one of the approaches was found to have a cracked foundation on March 9, 1989, it was closed to undergo temporary repairs for four days.

In 1990, the Port Authority announced a minor rehabilitation for the George Washington Bridge. As part of the project, the supporting structural steel for the upper deck would be replaced, and some ramps would be rebuilt. The ramps on the New York side, connecting with Riverside Drive and the Henry Hudson Parkway, were to be reconstructed for $27.6million after studies in the late 1980s showed deterioration on these ramps. Although the Port Authority had announced the repairs in advance, the start of roadwork in September 1990 caused extensive traffic jams. The upper deck was repaved in 1995, A further inspection in 1997 found that some of the wires at the New York anchorage had corroded, so these wires were replaced.

2000s to present
Starting on July 4, 2000, and for subsequent special occasions, each of the George Washington Bridge's suspension towers has been illuminated by 380 light fixtures that highlight the exposed steel structure. On each tower there are a mix of 150 and 1000 watt metal halide lamp fixtures. The architectural lighting design was completed by Domingo Gonzalez Associates.

In 1999, workers started rehabilitating about 5 miles of approach ramps; the project was finished in May 2001 and cost $38 million. Trucks were also banned from the lower deck around this time. The Port Authority also proposed a ramp from the lower level to the Palisades Interstate Parkway on the New Jersey side in 2000. Originally, the ramp would have cost $86.5million and would have been completed in 2003 or 2004. The connection was ultimately not built. The northern sidewalk was closed after the September 11 attacks in 2001 because of security concerns.

In 2002, the Port Authority began to repaint the towers and the underside of the upper deck. The old lead-based paint was replaced with a lead-free coat of paint. The $62 million project was completed in September 2006, in advance of the bridge's 75th anniversary. The Port Authority announced the next year that the suspender lighting was to be replaced by new energy efficient diodes. This project was completed in 2009.

In December 2011, the Port Authority announced plans to extensively rehabilitate the bridge.Of many improvements and repairs, the vertical suspender ropes would be replaced, at an expected cost of more than $1billion paid for by toll revenue. On August 5, 2013, repair crews began an $82-million effort to fix cracks in upper-deck structural steel caused by traffic, particularly heavy trucks. The plan called for replacing 632 road deck panels, which would add at least 20 years of service life to the roadway. The work proceeded at night, and was slated to be complete by year's end. Delays prevented completion, and ultimately the work was halted for the winter. Work restarted in June 2014 and was expected to last another 12 weeks. The Port Authority also started a $2 billion project to renovate or replace bridge components. The lower level was repaved in 2016, and repainting work and maintenance platform replacement on the lower deck was completed in 2017. The bridge's 592 vertical suspender ropes were then replaced to fix damage caused by excessive heat and humidity. The staircases leading to the sidewalks on both the northern and southern sides of the upper deck were also being replaced with ramps that were compliant with the Americans with Disabilities Act of 1990. The Trans-Manhattan Expressway was being renovated in conjunction with this project. On the New Jersey side, the Palisades Interstate Parkway “Helix” ramp onto the Bridge would be replaced at a cost of $112.6million by 2019. A temporary structure would be assembled through the duration of the work and dismantled afterwards, and two overpasses would also be rehabilitated. This was completed in March 2019. The northern sidewalk reopened in early 2023, after the suspender ropes on that side had been replaced. By early 2024, the restoration project was half complete, and workers were restoring the southern sidewalk and its cables.

New Jersey
The George Washington Bridge carries I-95 and US 1/9 between New Jersey and New York. Coming from New Jersey, US 46 terminates at the state border in the middle of the bridge. Further west, I-80, US 9W, New Jersey Route 4, and the New Jersey Turnpike also feed into the bridge via either I-95, U.S. 1/9, or U.S. 46 but end before reaching it. I-80 also gives drivers from the Garden State Parkway and Route 17 access to the bridge, and access to them as seen by signage on I-95 south. The Palisades Interstate Parkway connects directly to the bridge's upper level, though not to the lower level; however, a ramp to link the Interstate Parkway to the lower level was proposed in 2000. The marginal roads and local streets above the highways are known as GWB Plaza. The bridge's toll plaza, which collects tolls from eastbound/northbound traffic only, is located on the New Jersey side.

New York
On the New York side, the 12-lane Trans-Manhattan Expressway heads east across the narrow neck of Upper Manhattan, from the bridge to the Harlem River. It provides access from both decks to 178th and 179th Streets, which cross Manhattan horizontally, where U.S. 9 leaves the expressway and follows Broadway; the Henry Hudson Parkway and Riverside Drive, on the Hudson River's eastern bank along the west side of Manhattan; and to Amsterdam Avenue and the Harlem River Drive, on the Harlem River's western bank on the east side. The expressway connects directly with the Alexander Hamilton Bridge, which spans the Harlem River as part of the Cross-Bronx Expressway (I-95), providing access to the Major Deegan Expressway (I-87). Heading towards New Jersey, local access to the bridge is available from 179th Street. There are also ramps connecting the bridge to the George Washington Bridge Bus Terminal, a commuter bus terminal with direct access to the New York City Subway at the 175th Street station on the IND Eighth Avenue Line (served by the ).

Originally, the approach to the George Washington Bridge from the New York side consisted of a roundabout encircling a fountain, which was designed by Cass Gilbert. This plan was deemed not feasible as a result of the congestion that the weaving movements would create. The final plans called for meandering roadways from Riverside Drive and Henry Hudson Parkway, which run along the eastern bank of the Hudson River at the bottom of the cliff in Washington Heights. The Henry Hudson Parkway actually passes under the New York side's anchorage using an underpass designed by Gilbert. The connection to the 178th–179th Street Tunnels, which connected to the southbound Harlem River Drive, opened in 1940. The tunnels were replaced by the Trans-Manhattan Expressway, which opened in 1962. The tunnels and expressway were built to minimize disruption to the Washington Heights neighborhood, which had already been developed at the time.

Alternate routes
Further south along the Hudson River, the Lincoln Tunnel (Route 495) and Holland Tunnel (Interstate 78/Route 139) also enter Manhattan. Both tunnels are operated by the Port Authority, which collects tolls from drivers crossing the Hudson River eastbound toward New York City. The Verrazzano-Narrows Bridge (I-278), connecting the New York City boroughs of Staten Island and Brooklyn, is the southernmost alternate route. It connects to the Bayonne Bridge, Goethals Bridge, and Outerbridge Crossing between Staten Island and New Jersey. All four bridges to Staten Island collect tolls for drivers driving into the island.

Farther north within the New York metropolitan area, the Tappan Zee Bridge (Interstates 87/287 and New York State Thruway) avoids the congested Cross Bronx Expressway and the city proper. Thruway traffic sometimes uses the George Washington Bridge as a detour, since no roads cross the Hudson River between the George Washington and Tappan Zee bridges. The Tappan Zee Bridge also charges tolls for eastbound drivers. Even farther north is the Bear Mountain Bridge, carrying U.S. 6 and U.S. 202, about 20 mi north of the Tappan Zee Bridge; it also charges tolls for eastbound drivers.

Tolls
, the tolls-by-mail rate going from New Jersey to New York City are $17.63 for cars and motorcycles; there is no toll for passenger vehicles going from New York City to New Jersey. New Jersey and New York–issued E-ZPass users are charged $13.38 for cars and $12.38 for motorcycles during off-peak hours, and $15.38 for cars and $14.38 for motorcycles during peak hours. Users with E-ZPass issued from agencies outside of New Jersey and New York are charged the tolls-by-mail rate.

Originally, tolls were collected in both directions. The original toll booth was designed by Gilbert, who also designed a classical-style maintenance booth, neither of which is extant. In August 1970, the toll was abolished for westbound drivers, and at the same time, eastbound drivers saw their tolls doubled. The tolls of eleven other New York–New Jersey and Hudson River crossings along a 130 mi stretch, from the Outerbridge Crossing in the south to the Rip Van Winkle Bridge in the north, were also changed to south- or eastbound-only at that time. There were a series of tollbooths on the New Jersey side. The bridge had 29 toll lanes: 12 in the main upper-level toll plaza, 10 in the lower-level toll plaza, and seven in the Palisades Interstate Parkway toll plaza leading to the upper level. The toll plazas on the lower level and Palisades Parkway were not staffed during the overnight hours and accepted only E-ZPass transactions during this period. E-ZPass was accepted for toll payment on the George Washington Bridge starting in July 1997. Soon afterward, the Port Authority proposed removing the tollbooths for the E-ZPass lanes on the lower level and Palisades Parkway toll plazas, replacing them with electronic toll collection gantries to allow motorists to maintain highway speeds.

Pedestrians and cyclists may cross free of charge on the south sidewalk. Pedestrians traveling in either direction originally paid tolls of 10 cents when the bridge opened. The pedestrian toll was reduced to 5 cents in 1935 and discontinued altogether in 1940.

Open road tolling was implemented for drivers going from Palisades Interstate Parkway on February 2, 2020, on the lower level on November 7, 2020, and on the upper level on July 10, 2022. The tollbooths will be dismantled, and drivers will no longer be able to pay cash at the bridge. Instead, there will be cameras mounted onto new overhead gantries on the New Jersey side going to New York. A vehicle without E-ZPass will have a picture taken of its license plate and a bill for the toll will be mailed to its owner. For E-ZPass users, sensors will detect their transponders wirelessly. In March 2020, due to the COVID-19 pandemic, all-electronic tolling was temporarily placed in effect for all Port Authority crossings, including the George Washington Bridge. Cash toll collection was temporarily reinstated on the upper level only from October 2020 to July 2022 while the required open road tolling infrastructure was being installed. The carpool discount was eliminated when open-road tolling commenced on the upper level in July 2022.

Historic toll rates
Prior to July 10, 2022, a discounted carpool toll ($7.75) was available at all times for cars with three or more passengers using NY or NJ E-ZPass, who proceed through a staffed toll lane (provided they have registered with the free "Carpool Plan"), except if entering from the Palisades Interstate Parkway entrance to the bridge. The Carpool Plan ended when the George Washington Bridge implemented cashless tolling.

Non-motorized access
The George Washington Bridge contains two sidewalks that can be used by pedestrians and bicyclists. The southern sidewalk (accessible by a long, steep ramp on the Manhattan side of the bridge) is shared by cyclists and pedestrians. The entrance in Manhattan is at 178th Street, just west of Cabrini Boulevard, and also has access to the Hudson River Greenway north of the bridge. Both sidewalks are accessible on the New Jersey side from Hudson Terrace. The George Washington Bridge carries New York State Bicycle Route 9, a bike route that runs from New York City north to Rouses Point.

The Port Authority closed the northern sidewalk at all times in 2008. Though it offers direct access into Palisades Interstate Park, the northern sidewalk requires stairway climbs and descents on both sides, which was inaccessible for people with physical disabilities and posed a risk in poor weather conditions. Advocacy groups such as Transportation Alternatives also suggested improvements.

As part of the project to replace the bridge's vertical support cables, the connections to both sidewalks will be enhanced or rebuilt and made ADA-compliant. While the south-side cables are being replaced, that sidewalk will be closed and the north sidewalk will be open. Once the entire project is completed in 2027, pedestrians will use the south sidewalk and cyclists will use the north sidewalk. The sidewalk aspect of the project is expected to cost $118million.

Suicides and deaths
The George Washington Bridge is among the most frequently chosen sites in the New York metropolitan area for suicide by jumping or falling off the bridge. The first death by jumping occurred before the bridge even opened, though it was unintentional. On September 21, 1930, a stunt jumper named Norman J. Terry jumped off the bridge's deck in front of a crowd of thousands, but because his body was facing the wrong way, he broke his neck upon hitting the water. The first intentional suicide occurred on November 3, 1931, a little more than one week after the bridge opened.

Several suicide attempts off the George Washington Bridge have been widely publicized. In 1994, a person going by the name "Prince" called The Howard Stern Show while on the bridge, threatening to kill himself, but Stern managed to talk him out of it. The 2010 suicide of Tyler Clementi, who had jumped from the bridge, drew national attention to cyberbullying and the struggles facing LGBT youth.

In 2012, a record 18 people threw themselves off the bridge to their deaths, while 43 others attempted to do so but survived. There were 18 deaths reported in both 2014 and 2015. In 2014, 74 people were stopped by the Port Authority police, while the next year, another 86 people were stopped by the Port Authority police. In 2016, there were 12 reported deaths, a decrease from previous years, while 70 people were stopped by the Port Authority police. In 2017, the Port Authority proposed equipping a two-person Emergency Services Unit team with harnesses to prevent suicides from the bridge. Following 15 reported deaths and 68 attempts in 2017, the Port Authority installed protective netting and an 11 ft fence along each upper level sidewalk. The netting partially overhangs the sidewalks in order to prevent potential jumpers from scaling the fence directly. The southern sidewalk was closed from September to December 2017 so that a temporary fence could be installed there. Once the temporary fence had been erected, the permanent 11-foot-high barrier was constructed on the northern sidewalk, followed by the permanent barrier on the southern sidewalk.

Controversies and protests
From September 9 to 13, 2013, dedicated toll lanes for one of the local Fort Lee entrances to the bridge's upper level were reduced from three to one, with the two other lanes diverted to highway traffic, without notification to local government officials and emergency responders. The closures were made on the direction of aides and appointees of New Jersey Governor Chris Christie, causing a political controversy called "Bridgegate". The local toll lane reductions caused massive traffic congestion, with major delays for school transportation and police and emergency service responses within Fort Lee. The repercussions and controversy surrounding these actions have been investigated by the Port Authority, federal prosecutors, and a New Jersey legislature committee.

On September 12, 2020, a hundred anti-police brutality protesters from the Black Lives Matter movement converged from both New York and New Jersey, blocking the upper level of the bridge for about an hour before walking to the New York City Police Department's 34th Precinct in Manhattan.

Other incidents
On December 28, 1966, a 19-year-old pilot made an emergency landing on the bridge's New Jersey side after his plane's engine failed. There were no deaths reported, because there was very little traffic at the time, but the pilot and his passenger were injured. At the time, there was no median barrier on the bridge's upper deck.

In June 1977, two tractor-trailers nearly fell off the lower level after jackknifing, then going through both the roadway barrier and a mesh net next to the roadway. One of the drivers was hurt slightly, while the other driver was not hurt. The accident also involved a third tractor-trailer and two passenger cars, none of whose occupants were hurt. Accidents involving trucks dumping their cargo have also occurred on the George Washington Bridge. Watermelons, frozen chicken parts, and horse manure have all fallen onto the bridge's roadway at some point.

The first-ever complete closure of the George Washington Bridge occurred on August 6, 1980, when a truck carrying highly flammable propane gas across the bridge started to leak. As a safety precaution in case the fuel started to ignite, traffic across the bridge was halted for several hours, and 2,000 people living near the bridge were evacuated. Since the George Washington Bridge is the primary crossing between New Jersey and New York City, the closure caused traffic jams that stretched for up to 30 mi, and the effects of this congestion could be seen more than 45 mi away. Two police officers eventually plugged the leak with an inexpensive device. Up to that point, trucks carrying flammable material had been allowed to use the George Washington Bridge. After the incident, New York City officials conducted a study on whether to prohibit hazardous cargo from traveling through the city.

During the terrorist attacks on September 11, 2001, several news organizations, including CNN, reported that a vehicle filled with explosives had been found on the lower level of the bridge. However, several investigations found no evidence of a vehicle containing explosives on the bridge.

In popular culture
The bridge is seen in a number of movies set in New York:
 * Ball of Fire (1941) was the first film to show the bridge.
 * In Force of Evil (1948), Leo Morse is buried under the bridge by the mob of gangsters employing his brother Joe.
 * In How to Marry a Millionaire (1953), Loco and Brewster are fêted as being in the 50 millionth car to cross the bridge as part of the "George Washington Bridge Week" festivities.
 * In Network (1976), Schumacher tells a funny story in which, having overslept for a news shoot about the bridge's new lower deck, gets into a cab wearing a raincoat over his pajamas and tells the driver to take him to the middle of the bridge. The taxi driver, concerned that Schumacher intends to jump, begs him: "Don't do it buddy! You're a young man!"
 * Sully (2016) reenacts how Sullenberger overflew the bridge by a few hundred feet.
 * The bridge was also shown in The Godfather (1972), and Cop Land (1997).

The bridge has been featured in music. In the opening singalong for Sesame Street, Ernie sang the words "George Washington Bridge" to the tune of Sobre las Olas ("The Loveliest Night of the Year"). In addition, William Schuman's 1950 work George Washington Bridge. Nina Rosario sings "Just me and the GWB asking, 'Gee, Nina, what'll you be? in "Breathe" from In the Heights.

In visual art, the first issue of the comic Atomic War! published in November 1952, the George Washington Bridge is shown collapsing during a bombing of New York City. Additionally, painters George Ault and Valeri Larko have both created artworks named after the bridge. Video games such as Metal Gear Solid 2: Sons of Liberty also showed the George Washington Bridge.

The construction of the bridge is detailed in George Washington Bridge: A Timeless Marvel and George Washington Bridge: Poetry in Steel. The bridge and the nearby Little Red Lighthouse are the subjects of Hildegarde Swift's 1942 children's book The Little Red Lighthouse and the Great Gray Bridge.

title: George Washington Bridge


text:
Lippe (river)

The Lippe is a river in North Rhine-Westphalia, Germany. It is a right tributary of the Rhine and 220.3 km in length with an elevation difference of 125 metres and a catchment area of 4.890 km². The source is located at the edge of the Teutoburg Forest in Bad Lippspringe close to the city of Paderborn. It runs westward through Paderborn, Lippstadt and then along the northern edge of the Ruhr area, parallel to the river Emscher and river Ruhr. The river finally enters the Rhine at Wesel.

Description and history
The river Lippe has been used as an infrastructure in Roman times. For the Romans the river (named Lupia) was a gateway to Germania, running from the river Rhine to the region around Paderborn. The watercourse was used for transport of supplies, so along the banks of the Lippe many former Roman camps could be found. In the last 200 years many of these camps have been identified, above all the camp in Haltern which is likely to be the former headquarter of the imperial prince Tiberius. The distance between the camps is about a one-day walk for the troops, which is almost 30 km (20 mi). Today's identified Roman camps are: Olfen, Xanten, Haltern, Oberaden, Holsterhausen, Anreppen and Beckinghausen. The Battle of the Lupia River was fought in 11 BCE between Nero Claudius Drusus and the Sicambri (Sugambri).

Today, the river appears as a two-tier water course: Upstream, eastward of the city of Hamm, the catchment is more rural. Downstream of Hamm settlements and industrial impacts characterize the situation. Though the Lippe was partly navigable from 1820 on it was not sufficient for the transport of industrial goods.

Historically, the preconditions for a change of the landscape started with the construction of the Cologne-Minden trunk line in the 1840s that connected the river Rhine settlements like Cologne with harbours and trade at the river Weser and so with the Lippe town Hamm, too. Moreover, this railway supported the coal and steel industry development in the northern Ruhr region. The hard coal mining that started in the middle of the 19th century in the Emscher catchment area developed in the following decades direction north and so to the Lippe catchment area. From the 1860s onwards the first problems of mining subsidence and drainage of polluted water appeared. The historical city of Hamm and the towns Lünen, Haltern and Dorsten were small settlements located at the Lippe but expanded with the establishment of hard coal mines starting around 1900. The industrialization caused huge water quality problems in the Lippe tributaries and the Lippe itself; therefore first in 1913 the Sesekegenossenschaft and later in 1926 the Lippeverband  (“Wasserwirtschaftsverbände”) were established as water boards. Since 1914 the Datteln-Hamm Canal and 1930 the Wesel-Datteln Canal are located in parallel to the Lippe which is not navigable for mass transportation. The canals receive Lippe water or feed the Lippe (to improve dry weather flow) from an exchange facility in Hamm, operated by the Wasserverband Westdeutsche Kanäle.

Until the 1970s water pollution played no important role in the public debate but the environmental policy changed over the decades. Environmental standards on national level and especially from the EU have been leading to enormous efforts to improve the natural standards and today a couple of positive developments can be stated, like new FFH (Flora Fauna Habitat) sites and governmental initiatives around the WFD (Water Framework Directive).

Tributaries
The main tributaries of the Lippe are (from source to mouth):
 * Left: Steinbeke, Beke, Pader, Alme, Heder, Brandenbaumer Bach, Gieseler, Trotzbach, Ahse, Seseke, Sickingmühlenbach
 * Right: Thunebach, Thune, Glenne, Baagebach, Quabbe, Geinegge, Stever

Cities and towns

 * Towns: Wesel, Dorsten, Marl, Lünen and Haltern
 * Cities: Paderborn, Lippstadt and Hamm

title: Lippe (river)


text:
Lists of airlines

Lists of airlines cover existing and defunct airlines. Complete lists are given in alphabetical sequence by the name of the continent from which they operate. Lists are also given by size, by business model and by other characteristics. There are over 5,000 airlines with ICAO codes.

By continent
Lists of airlines based on continent:
 * List of airlines of Africa
 * List of airlines of the Americas
 * List of airlines of Asia
 * List of airlines of Europe
 * List of airlines of Oceania

By size and continent

 * List of largest airlines in the world
 * List of largest airlines in Africa
 * List of largest airlines in Asia
 * List of largest airlines in Central America & the Caribbean
 * List of largest airlines in Europe
 * List of largest airlines in North America
 * List of largest airlines in Oceania
 * List of largest airlines in South America

By business model

 * List of government-owned airlines
 * List of passenger airlines
 * List of charter airlines
 * List of low-cost airlines
 * List of regional airlines

By other characteristics

 * Flag carrier
 * List of airlines by foundation date
 * List of airlines with more than 100 destinations
 * List of defunct airlines
 * List of helicopter airlines
 * List of airline codes
 * List of government-owned airlines

title: Lists of airlines


text:
1918 in sports

 * Note — many sporting events did not take place because of World War I or the 1918 flu pandemic

1918 in sports describes the year's events in world sport.

American football
College championship Professional football
 * College football national championship – Pittsburgh Panthers
 * Most teams shut down due to World War I and the flu pandemic; those that continue play are forced to delay the start of play until the middle of October or later
 * Dayton Triangles defeat Detroit Heralds, both of whom continue full operations despite war and flu, to establish themselves as the strongest team in the US
 * Buffalo Niagaras sign Tommy Hughitt for play in a citywide league, establishing a trend of expansion of top-level professional competition outside Ohio

Association football
Europe
 * There is no major football in Europe due to World War I

Australian rules football
VFL Premiership South Australian Football League: West Australian Football League:
 * South Melbourne wins the 22nd VFL Premiership beating Collingwood 9.8 (62) to 7.15 (57) in the 1918 VFL Grand Final.
 * not contested due to World War I
 * 21 September: East Fremantle 11.8 (74) defeat East Perth 8.5 (53) for their tenth WAFL premiership.

Bandy
Sweden
 * Championship final – IFK Uppsala 4–1 IK Sirius (replay following 2–2 draw)

Baseball
World Series Events
 * 5–11 September — Boston Red Sox (AL) defeats Chicago Cubs (NL) to win the 1918 World Series by 4 games to 2
 * Babe Ruth leads the American League in home runs for the first time, hitting 11
 * 2 September — professional baseball is curtailed to accelerate mobilisation for war

Boxing
Events Lineal world champions
 * No world titles change hands in 1918 but Jack Dempsey, with a series of knockouts including one against Battling Levinsky, is now the main challenger to Jess Willard.
 * World Heavyweight Championship – Jess Willard
 * World Light Heavyweight Championship – Battling Levinsky
 * World Middleweight Championship – Mike O'Dowd
 * World Welterweight Championship – Ted "Kid" Lewis
 * World Lightweight Championship – Benny Leonard
 * World Featherweight Championship – Johnny Kilbane
 * World Bantamweight Championship – Pete Herman
 * World Flyweight Championship – Jimmy Wilde

Canadian football
Grey Cup
 * not contested due to World War I

Cricket
Events India New Zealand
 * There is no first-class cricket in England, Australia, South Africa or the West Indies due to World War I. A number of first-class matches are arranged in New Zealand but are not part of any official competition.
 * Bombay Quadrangular – Hindus shared with Parsees
 * Plunket Shield – not contested

Cycling
Tour de France Giro d'Italia
 * not contested due to World War I
 * not contested due to World War I

Figure skating
World Figure Skating Championships
 * not contested due to World War I

Golf
Events
 * All major championships are cancelled due to World War I

Horse racing
England Australia Canada Ireland USA
 * Grand National – not held due to World War I
 * 1,000 Guineas Stakes – Ferry
 * 2,000 Guineas Stakes – Gainsborough
 * The Derby – Gainsborough
 * The Oaks – My Dear
 * St. Leger Stakes – Gainsborough
 * Melbourne Cup – Night Watch
 * King's Plate – Springside
 * Irish Grand National – Ballyboggan
 * Irish Derby Stakes – King John
 * Kentucky Derby – Exterminator
 * Preakness Stakes – not contested as a single race
 * Belmont Stakes – Johren

Ice hockey
Stanley Cup Events
 * The temporary Toronto Arenas team defeats the Montreal Canadiens 10–7 to win the inaugural National Hockey League (NHL) championship
 * Vancouver Millionaires defeats Seattle Metropolitans 3–2 to win the Pacific Coast Hockey Association championship
 * 20–30 March — Toronto Arenas (NHL) defeats Vancouver Millionaires (PCHA) in the 1918 Stanley Cup Finals by 3 games to 2
 * 2 January — Montreal Wanderers disbands following destruction of its home venue by fire
 * Allan Cup is won by Kitchener Greenshirts

Motor racing
Events
 * No major races are held anywhere worldwide due to World War I

Rowing
The Boat Race
 * Oxford and Cambridge Boat Race – not contested due to World War I

Rugby league
England Australia New Zealand
 * All first-class competitions are cancelled due to World War I
 * NSW Premiership – South Sydney (outright winner)
 * 1918 New Zealand rugby league season

Rugby union
Five Nations Championship
 * Five Nations Championship series is not contested due to World War I

Speed skating
Speed Skating World Championships
 * not contested due to World War I

Tennis
Australia England France USA Davis Cup
 * Australian Men's Singles Championship – not contested due to World War I
 * Wimbledon Men's Singles Championship – not contested due to World War I
 * Wimbledon Women's Singles Championship – not contested due to World War I
 * French Men's Singles Championship – not contested due to World War I
 * French Women's Singles Championship – not contested due to World War I
 * American Men's Singles Championship – Lindley Murray (USA) defeats Bill Tilden (USA) 6–3 6–1 7–5
 * American Women's Singles Championship – Molla Bjurstedt Mallory (Norway) defeats Eleanor E. Goss (USA) 6–4 6–3
 * 1918 International Lawn Tennis Challenge – not contested

title: 1918 in sports


text:
Agricultural productivity

Agricultural productivity is measured as the ratio of agricultural outputs to inputs. While individual products are usually measured by weight, which is known as crop yield, varying products make measuring overall agricultural output difficult. Therefore, agricultural productivity is usually measured as the market value of the final output. This productivity can be compared to many different types of inputs such as labour or land. Such comparisons are called partial measures of productivity.

Agricultural productivity may also be measured by what is termed total factor productivity (TFP). This method of calculating agricultural productivity compares an index of agricultural inputs to an index of outputs. This measure of agricultural productivity was established to remedy the shortcomings of the partial measures of productivity; notably that it is often hard to identify the factors cause them to change. Changes in TFP are usually attributed to technological improvements.

Agricultural productivity is an important component of food security. Increasing agricultural productivity through sustainable practices can be an important way to decrease the amount of land needed for farming and slow environmental degradation and climate change through processes like deforestation.

Sources of agricultural productivity
Productivity is driven by changes in either agricultural technique or improvements in technology. Some sources of changes in agricultural productivity have included:
 * Mechanization
 * High yield varieties, which were the basis of the Green revolution
 * Fertilizers: Primary plant nutrients: nitrogen, phosphorus and potassium and secondary nutrients such as sulfur, zinc, copper, manganese, calcium, magnesium and molybdenum on deficient soil
 * Education in management and entrepreneurial techniques to decrease fixed and variable costs and optimise manpower
 * Liming of acid soils to raise pH and to provide calcium and magnesium
 * Irrigation
 * Herbicides
 * Genetic engineering
 * Pesticides
 * Increased plant density
 * Animal feed made more digestible by processing
 * Keeping animals indoors in cold weather

See: Productivity improving technologies (historical) Section: 2.4.1: Mechanization: Agriculture, Section 2.6: Scientific agriculture.

Impact
The productivity of a region's farms is important for many reasons. Aside from providing more food, increasing the productivity of farms affects the region's prospects for growth and competitiveness on the agricultural market, income distribution and savings, and labour migration. An increase in a region's agricultural productivity implies a more efficient distribution of scarce resources. As farmers adopt new techniques and differences, the more productive farmers benefit from an increase in their welfare while farmers who are not productive enough will exit the market to seek success elsewhere. As a region's farms become more productive, its comparative advantage in agricultural products increases, which means that it can produce these products at a lower opportunity cost than can other regions. Therefore, the region becomes more competitive on the world market, which means that it can attract more consumers since they are able to buy more of the products offered for the same amount of money. As productivity improvement leads to falling food prices, this automatically leads to increases in real income elsewhere.

Increases in agricultural productivity lead also to agricultural growth and can help to alleviate poverty in poor and developing countries, where agriculture often employs the greatest portion of the population. As farms become more productive, the wages earned by those who work in agriculture increase. At the same time, food prices decrease and food supplies become more stable. Labourers therefore have more money to spend on food as well as other products. This also leads to agricultural growth. People see that there is a greater opportunity to earn their living by farming and are attracted to agriculture either as owners of farms themselves or as labourers. It is not only the people employed in agriculture who benefit from increases in agricultural productivity. Those employed in other sectors also enjoy lower food prices and a more stable food supply. Their wages may also increase.

Food security
Agricultural productivity is becoming increasingly important as the world population continues to grow. As agricultural productivity grows, food prices decrease, allowing people to spend less on food, and combatting hunger. India, one of the world's most populous countries, has taken steps in the past decades to increase its land productivity. In the 1960s North India produced only wheat, but with the advent of the earlier maturing high-yielding wheats and rices, the wheat could be harvested in time to plant rice. This wheat/rice combination is now widely used throughout the Punjab, Haryana, and parts of Uttar Pradesh. The wheat yield of three tons and rice yield of two tons combine for five tons of grain per hectare, helping to feed India's 1.1 billion people.

Higher global food prices between 2006 and 2008, primarily caused by an increasing amount arable land used for growing biofuels and the growing economies in China and elsewhere causing an increase in demand for meat products (which are less efficient than plants in terms of land use), caused the percentage of incomes used for food to increase throughout the world, forcing families to cut back on various other expenditures such as schooling for girls. In areas of sub-Saharan Africa, a decreased agricultural productivity due to crop failures has caused starvation. On the other hand, higher global prices actually mean farmers with successful yields earn more, and this thus increases their productivity.

Investing in the agricultural productivity of women in farming communities is of particular importance in boosting economic development and food security in parts of the developing world. Women in some areas of the world, for example in Africa, traditionally have less agency than men, but are often also more invested in farming in terms of time spent. They are furthermore generally more responsible for childcare, thus their productivity is more likely to translate in gains for the family as a whole.

Relation to population growth
Some critics claim that increasing agricultural productivity results in human overpopulation. They are argue that, like other species, human populations grow up to their carrying capacity. When a species reaches its carrying capacity, the number of poor and weak individuals who die from disease or starvation is equal to the number of individuals being added to the population via birth. Because innovation continues to improve agricultural productivity (specifically yields), however, the theoretical carrying capacity continues to increase, allowing the human population to continue to grow. These writers claim that there are too many people on Earth and that therefore growth in agricultural productivity is detrimental to the environment — if the carrying capacity was lower, the human population would reach an equilibrium at a lower number.

However, unlike other animals, in humans greater development and prosperity has led to lower fecundity. Thus as productivity has increased and poverty has been reduced worldwide, population growth is declining. Research suggests we may actually face a declining world population in the future.

Inverse relationship theory
Deolalikar in 1981 investigated the theory first proposed by Sen in 1975 that in traditional, pre-modern farming in India, there is an inverse relationship to size of the farm and productivity, contrary to the economy of scale found in all other types of economic activity. It is debated whether the inverse relationship actually exists. Numerous studies falsify this theory. In Zimbabwe, policies on agrarian land reform under president Robert Mugabe, especially in and following 2000, split large farms into many smaller farms, and this decreased productivity. Marxist agrarian land reform in the Soviet Union, China and Vietnam combined small farms into larger units, this usually failed to increase productivity.

Nonetheless, increasing agricultural productivity amongst smallholder farms is an important way to improve farmer livelihoods in the developing world.

Sustainable increases in productivity
Because agriculture has such large impacts on climate change and other environmental issues, intensification of agriculture, which would increase productivity per amount of land being farmed, is seen by some as an important method for climate change mitigation, because farmers will not require more land, and are thus incentivized not to participate in further land degradation or deforestation. Implementing intensification through sustainable agriculture practices makes farming more sustainable in the long term, maintaining the ability of the future generations to meet their own needs while conserving the environment. International policy, embodied in Sustainable Development Goal 2, focusses on improving these practices at an international level.

Not all effects of climate change will be negative on agricultural productivity. The IPCC Special Report on Climate Change and Land and the Special Report on Global Warming of 1.5 °C both project mixed changes in the yields of crops as global warming happens with some breadbasket regions becoming less productive, while other crops increase ranges and productivity.

title: Agricultural productivity


text: IMNSHO

title: IMNSHO