The Golden Gate Bridge is an iconic bridge that connects San Francisco to Marin County. It is an American icon whose symbolism power rivals that of the Empire State Building and Statue of Liberty. The American Society of Civil Engineers designated the bridge as one of the seven wonders of the United States in 1994.
Construction
The construction of the Golden Gate Bridge was started in 1933 and completed after four years. It is 1.7 miles long and 90 feet wide. The area is an earthquake zone, and throughout the year, it faces rough waters, high winds, and fierce storms. Joseph Strauss and his two engineering consultants, Charles Ellis and Leon Moisseiff, determined that a suspension bridge would be the best fit for the Golden Gate.
The anchorages were made of thick cement, and they hold the ends of the giant cables at opposite shores, “anchoring” the bridge to the ground. The two towers of the bridge were made of steel. The roadway in a suspension bridge is suspended or hung from strong wire cables. The cables are flexible, allowing the bridge to expand and contract in hot and cold weather and swing in high winds without breaking.
Opening
Eighteen hundred cars and 2,100 pedestrians crossed in the first hour of its operation. By midnight of opening day, an estimated 25,000 vehicles and 19,350 pedestrians had paid their tolls (fifty cents per car, five cents per pedestrian). By the end of its first fiscal year, 3,326,521 vehicles had crossed. By the end of 1970, the annual number was 33 million.
Here below are amazing historical photos that show the construction of the iconic structure.
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