Brooklyn Bridge. The Brooklyn Bridge is a hybrid cable-stayed, suspension bridge in New York City, spanning the East River between the boroughs of Manhattan and Brooklyn. Opened on May 24, 1883, the Brooklyn Bridge was the first fixed crossing across the East River. It was also the longest suspension bridge in the world at the time, with a main span of 1,595.5 feet and a deck height of 127 ft above mean high water. The span was originally called the New York and Brooklyn Bridge or the East River Bridge but was officially renamed the Brooklyn Bridge in 1915. Proposals for a bridge connecting Manhattan and Brooklyn were first made in the early 19th century, which eventually led to the construction of the current span, designed by John A. Roebling. His son Washington Roebling oversaw the construction and contributed further design work, assisted by the latter's wife, Emily Warren Roebling. While construction started in 1870, numerous controversies and the novelty of the designed construction process caused the actual construction to be prolonged over thirteen years. Since opening, the Brooklyn Bridge has undergone several reconfigurations, having carried horse-drawn vehicles and elevated railway lines until 1950. To alleviate increasing traffic flows, additional bridges and tunnels were built across the East River. Following gradual deterioration, the Brooklyn Bridge has been renovated several times, including in the 1950s, 1980s, and 2010s. The Brooklyn Bridge is the southernmost of four toll-free vehicular bridges connecting Manhattan Island and Long Island, with the Manhattan, Williamsburg, and Queensboro Bridges to the north. Only passenger vehicles and pedestrian and bicycle traffic are permitted. A major tourist attraction since its opening, the Brooklyn Bridge has become an icon of New York City. Over the years, the bridge has been used as the location of various stunts and performances, as well as several crimes and attacks. The Brooklyn Bridge has been designated a National Historic Landmark, a New York City landmark, and a National Historic Civil Engineering Landmark. The Brooklyn Bridge, the world's first major steel-wire suspension bridge, uses a hybrid cable-stayed /suspension bridge design, with both horizontal and diagonal suspender cables. Its stone towers are neo-Gothic, with characteristic pointed arches. The New York City Department of Transportation, which maintains the bridge, says that its original paint scheme was Brooklyn Bridge Tan and Silver, although a writer for The New York Post states that it was originally entirely Rawlins Red. To provide sufficient clearance for shipping in the East River, the Brooklyn Bridge incorporates long approach viaducts on either end to raise it from low ground on both shores. Including approaches, the Brooklyn Bridge is a total of 6,016 feet long when measured between the curbs at Park Row in Manhattan and Sands Street in Brooklyn. A separate measurement of 5,989 feet is sometimes stated, the distance from the curb at Centre Street in Manhattan. The main span between the two suspension towers is 1,595.5 feet long and 85 feet wide. Navigational clearance is 127 ft above mean high water. During construction, Joseph Henderson, a harbor pilot regarded as one of the most experienced and trustworthy of New York's Sandy Hook Pilots, had been asked to determine the height above MHW for the Brooklyn Bridge's main span. A 1909 Engineering Magazine article said that, at the center of the span, the height above MHW could fluctuate by more than 9 feet due to temperature and traffic loads, while more rigid spans had a lower maximum deflection. The side spans, between each suspension tower and each side's suspension anchorages, are 930 feet long. At the time of construction, engineers had not yet discovered the aerodynamics of bridge construction, and bridge designs were not tested in wind tunnels. It was coincidental that the open truss structure supporting the deck is, by its nature, subject to fewer aerodynamic problems. This is because John Roebling designed the Brooklyn Bridge's truss system to be six to eight times as strong as he thought it needed to be.
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