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Construction Of The Golden Gate Bridge

Before the Golden Gate Bridge was constructed, San Francisco was a relatively isolated city. It sat at the top of a peninsula, surrounded on three sides by water that was difficult to cross. The “Golden Gate” itself is a narrow strip of water at the mouth of the San Francisco Bay. With strong currents and a depth of 400 feet, the Golden Gate strait is foreboding to sailors. On the other hand, circumnavigating the whole San Francisco Bay has its drawbacks too: the trip is hundreds of miles long and involves crossing several rivers, which can become shallow sand traps. *For these reasons, ferry service between San Francisco and Marin County began in 1820. First the ferry was only for railroad passengers, but later on people could bring their automobiles in tow. This became booming business. *When bridge proposals became serious, the ferry companies, including the Southern Pacific Railroad Company, opposed any bridge as competition. The military also objected to spanning the San Francisco Bay; they questioned whether the bridge would interfere with war ships. People in general wondered about the sturdiness of a suspension bridge, which is held by cables and strung between towers. Could such a bridge withstand the Bay’s strong gusts of wind? How would the bridge remain rooted in the ocean floor? *Nonetheless, by the 1900s it was evident that ferries alone could not handle travel demands. The city’s growth would be restricted until it overcame obstacles to trading with Northern California. In 1916 the Chicago-based engineer Joseph Strauss responded to San Francisco’s call for bridge submissions. Immediate local support mixed with alleged bribery helped him secure support from the city council. Strauss personally traveled north, too, to lobby Marin County council members and business people. He assured them that once a bridge was built from San Francisco, their businesses and property values would grow. He gained their support. By 1932, the founder of San Francisco-based Bank of America agreed to finance the estimated $30 million project. Work started in 1933.*The Golden Gate Bridge blueprints were improved upon since Strauss’s original submission. Strauss had little experience with suspension style bridges, so he hired a team of architects who made significant contributions. Today, the Purdue professor Charles Ellis is widely recognized as being the main architect behind the bridge, while Strauss is regarded as its organizer and promoter. A San Francisco architect named Irving Morrow, who was part of Strauss’s team, also made important contributions. He suggested painting the bridge a color he called “international orange”. This would complement the surrounding blues and greens of nature, and simultaneously make the bridge visible through fog. (If the bridge coloring had been left to the government or Strauss, it would likely have been black.) Irving also designed the bridge’s arches to play with light throughout the day, making the bridge especially pleasing to the eye. Electric lighting along the cables adds to the visual appeal at night.*The project was completed within four years and under budget at $27 million. The final project was built to withstand the Bay’s high winds; it can sway 27 feet and still safely hold traffic. It has only been closed a few times since 1937 when winds reached 70 miles per hour. *Today, ferry service continues between San Francisco and Marin County, but the Golden Gate Bridge carries over 40 million passengers each year. *