Golden Gate Bridge
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Location: San Francisco and Sausalito, California, USA
Completion Date: 1937
Cost: $27 million
Length: 8,981 feet
Materials: Steel, concrete
Longest Single Span: 4,200 feet
Engineer(s): Joseph B. Strauss
Today, some call it the "most spectacular bridge in the world." But a century ago, building the Golden Gate Bridge seemed like an impossible task. Any bridge in this location would have to withstand brutal winds, tide, and fog. It would also sit less than eight miles from the epicenter of the most catastrophic earthquake in history. Only one engineer was willing to gamble that his bridge could withstand such destructive power. His name was Joseph Strauss.
Strauss used more than one million tons of concrete to build the anchorages -- the massive blocks that grip the bridge's supporting cables. The north pier, which supports the tower, was built easily on a bedrock ledge 20 feet below the water. But on the southern San Francisco side, Strauss had to build his pier in the open ocean, 100 feet below the surface. He built a huge water-tight cofferdam -- big enough to enclose a football field -- and pumped in hundreds of tons of concrete. By 1935, the towers were complete, and cable-spinning began. Two years later, the bridge was finished.
Strauss completed the $27 million bridge only five months after the promised date and $1.3 million under budget. For his efforts, Strauss received $1 million and a lifetime bridge pass.