| Fact file |
When built: Completed 1937
Height: 227m above water
Length: 2,737m
Weight: 80,470 tons
Workforce: Unknown, but 11 men died during construction
Project timescale: Four years
Construction material: Steel
Number of rivets: Approximately 600,000 in each tower.
Capacity: By 2002, 1.7 billion vehicles had crossed the bridge
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One of the world’s most recognisable structures, the Golden Gate Bridge was also the longest spanning bridge for 27 years after it was finished in 1937. It is a gravity-anchored suspension bridge, with 1,280m of open water passing beneath its two soaring steel cantilevers.
Joseph Strauss is largely accredited as the project’s visionary and lead engineer, however, engineer Charles Ellis and designer Leon Moissieff played a huge role in the success of this iconic crossing. With just a slide rule and an adding machine their calculations solved the problems of compression and tension that the project faced.
Slung between two elegant towers, the bridge’s two main cables each weigh 11,000 tons, made from over 25,000 individual wires. As well as holding up the suspended road, the cables also transfer compression into the towers, and the bridge’s anchors at either end of the construction.
An instant success, the Golden Gate Bridge had repaid its $75m cost by 1971 – only ever charging a toll to visitors heading south into San Francisco. In the last seven decades, it’s withstood countless earthquakes, including the devastating 7.1 quake of 1989. In fact, the bridge has only been closed three times in its entire history - by high winds.
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