Williamsburg Bridge

     The Williamsburg Bridge is a suspension bridge in New York City across the East River connecting the Lower East Side of Manhattan at Delancey Street with the Williamsburg neighborhood of Brooklyn at Broadway near the Brooklyn-Queens Expressway. It once carried New York State Route 27A and was planned to carry Interstate 78, though these plans were aborted by the cancellation of the Lower Manhattan Expressway and Bushwick Expressway.

      This is one of four toll-free crossings between Manhattan and Brooklyn or Queens.

George Washington Bridge

       The George Washington Bridge is a double-decked suspension bridge spanning the Hudson River, connecting the Washington Heights neighborhood in the borough of Manhattan in New York City to Fort Lee, Bergen County, New Jersey, in the United States. Interstate 95 (I-95) and U.S. Route 1/9 (US 1/9) cross the river via the bridge. 

       The bridge, an integral conduit within the New York metropolitan area, has an upper level carrying 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 (72 km/h), though congestion often slows traffic, especially during the morning and evening rush hours. The bridge's upper level carries pedestrian and bicycle traffic. 

        The George Washington Bridge carries approximately 102 million vehicles per year, making it the world's busiest motor vehicle bridge.

                                                Designer:         Othmar Ammann, Cass Gilbert
                                                Total length      4,760 ft (1,450 m)
                                                Width              119 ft (36 m)
                                                Height              604 ft (184 m)

                                           

Manhattan Bridge

     The Manhattan Bridge is a suspension bridge that crosses the East River in New York City,connecting Lower Manhattan with Brooklyn.It was the last of the three suspension bridges built across the lower East River, following the Brooklyn and the Williamsburg bridges. The bridge was opened to traffic on December 31, 1909 and was designed by Leon Moisseiff,who later designed the infamous original Tacoma Narrows Bridge that opened and collapsed in 1940. It has four vehicle lanes on the upper level. The lower level has three lanes, four subway tracks, a walkway and a bikeway. The upper level, originally used for streetcars, has two lanes in each direction, and the lower level is one-way and has threelanes in peak direction. It once 

carried New York State Route 27 and later was planned tocarry Interstate 478. No tolls are charged for motor vehicles to use the Manhattan Bridge.

Construction started          October 1, 1901
Opened to traffic               December 31, 1909
Length of main span          1,470 ft.
Total length of bridge
including approaches         6,855 ft.
Location                           Connects Flatbush Avenue in Downtown
                                        Brooklyn with Canal Street in Chinatown

Brooklyn Bridge

     The Brooklyn Bridge is a bridge in New York City and is one of the oldest suspension bridges in the United States. Completed in 1883, it connects the boroughs of  Manhattan and Brooklyn by spanning the East River. With a main span of 1,595.5 feet (486.3 m), it was the longest suspension bridge in the world from its opening until 1903, and the first steel-wire suspension bridge.

    The Brooklyn Bridge was initially designed by German immigrant John Augustus Roebling, who had previously designed and constructed shorter suspension bridges.While conducting surveys for the bridge project, Roebling sustained a crush injury to his foot when a ferry pinned it against a piling. After amputation of his crushed toes he developed a tetanus infection which left him incapacitated and soon resulted in his death, not long after he had placed his 32-year-old son Washington Roebling in charge of the project.

     Washington Roebling also suffered a paralyzing injury as a result of decompression sickness shortly after the beginning of construction on January 3, 1870. This condition, first called "caisson disease" by the project physician Andrew Smith, afflicted many of the workers working within the caissons.After Roebling's debilitating condition left him unable to physically supervise the construction firsthand, his wife Emily Warren Roebling stepped in and provided the critical written link between her husband and the engineers on site.Under her husband's guidance, Emily studied higher mathematics, the calculations of catenary curves, the strengths of materials, bridge specifications, and the intricacies of cable construction. She spent the next 11 years assisting Washington Roebling helping to supervise the bridge's construction. 

     The Brooklyn Bridge was opened for use on May 24, 1883. The opening ceremony was attended by several thousand people and many ships were present in the East Bay for the occasion. On that first day, a total of 1,800 vehicles and 150,300 people crossed what was then the only land passage between Manhattan and Brooklyn. Emily Warren Roebling was the first to cross the bridge. The bridge cost $15.5 million to build and an estimated number of 27 people died during its construction.