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Perhaps the best known suspension bridge in the world is the Golden Gate Bridge which spans across the entrance to the San Francisco Bay. Since completion in 1937, the Golden Gate Bridge has been a San Francisco landmark.
The Golden Gate Bridge was envisioned in 1917 by engineer Joseph Baermann Strauss. Strauss confronted 12 years of opposition to the idea of bridging the Golden Gate. Military leaders and shippers were concerned that the bridge would bottle up the harbor and ferryboat operators feared for their livelihood. He finally sold the public on the idea and in 1930 six coastal counties approved bonds to build the Golden Gate Bridge. Construction began in 1933 with the North Pier. Even then, the pier was the subject of intense debate over the question of whether the structure could withstand an earthquake. The foundation for the North Pier extends 100 feet below the surface and 35 feet into the bedrock.
The South Pier (San Francisco) was built on an uneven, sloping rock floor. The giant cables were spun into place from the anchorages in mid span. The Golden Gate Bridge was opened in May 1937 for a total cost of $33 million. It was designed as a bending bridge capable of 21 foot sway and a 10 foot sag and can support the weight of bumper to bumper cars and trucks in all six lanes and pedestrians packed on the walkways.
Since original construction, the bridge has been through several major rehabilitations. The first major rehabilitation was in 1953 when the bridge's deck was stiffened with lateral and steel bracing to increase torsional resistance. Furthermore, over the years, salt produced deterioration of the original concrete deck. In 1985, the bridge was resurfaced with a lighter, stronger material, reducing the stress on the cables and anchorages for a cost of $52.5 million.
Other landmarks: Christ the Redeemer, Colossus, Delhi pillar, Eiffel tower, Golden Gate bridge, Great Buddha, Guggenheim Museum (Bilbao), Guggenheim Museum (NYC), Normandy bridge, Oresund crossing, Quebec Bridge, Statue of Liberty, Thames Barrier, Titanic, Tower of the Orologio, Washington Monument
