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Bridges & Tunnels

Bridges

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    This is the Golden bridge in San francisco first called "Chrysopylae which means golden gate. The golden gate bridge is the nineth longest bridge in the world.Total length:1.7 miles (8,981 feet or 2,737 m) Width: 90 feet (27 m) Total weight today: 887,000 tons (804,700,000 kg)Total weight when built: 894,500 tons .
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     This is the tower bridge in London.The bridge was officially opened on 30 June 1894. The bridge consists of two towers tied together at the upper level by means of two horizontal walkways, designed to withstand the horizontal forces exerted by the suspended sections of the bridge on the landward sides of the towers. Total length:244 metres (801 ft). Longest span:61 metres (200 ft)
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       The Brooklyn Bridge is one of the oldest suspension bridges in the United States.Completed in 1883, it connects the New York City boroughs of Mannhattan and  Brooklyn  by spanning the East River. Total length:5,989 feet (1825 m) Width:85 feet (26 m)

Tunnels

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This is " the Holland Tunnel ".
In 1906, a coalition of the New York State Bridge and Tunnel Commission and the New Jersey Interstate Bridge and Tunnel Commission began feasibility studies for a bridge from lower Manhattan to Jersey City, New Jersey. It open in 1910,the tunnel measuring 31 feet in diameter. The upper level, which was to carry slower vehicles, was to have an 18�-foot-wide roadway and a clearance of 12 feet, flanked by sidewalks measuring 4� feet wide. The lower level, which was to be reserved for express vehicles, was to have a 16-foot-wide roadway and a nine-foot clearance. Both levels were to carry two-carry traffic.

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This is "Black Rock Tunnel". This was an active rail road tunnel of the old "Reading RailRoad". The 1835 tunnel was the second rail tunnel constructed in the U.S. , and is the oldest still in use.The Black Rock Tunnel was constructed between 1835 and 1837 and opened in 1838.
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This the "Flat Rock Tunnel ". The Flat Rock Tunnel is an active railroad tunnel near Manayunk, Pennsylvania, USA. The tunnel was built by the Reading Railroad for its line along the Schuylkill River.Construction of the tunnel started in 1836 and it opened in 1840.