The purpose of the Golden Gate Bridge is to connect San Francisco to Marin County, Calif. Before the bridge opened in 1937, the only practical route between what is now Marin County and San Francisco was by ferry across San Francisco Bay. At the time, San Francisco was the largest U.S. city reached primarily by ferry.Continue Reading
Ferry service across the bay began around 1820. By the late 1920s, the Golden Gate Ferry Company was the world's largest ferry operation. San Francisco's growth rate before the bridge was built was lower than the national average because the city lacked an easy route to other cities around the bay.
Some experts believed that it was impossible to build a bridge across the bay, which is 6,700 feet wide. The bay had strong tides and currents, and water reached a depth of 372 feet at the center. Some experts felt that the frequent strong winds and fog prevented building and operating the bridge.
In 1933, construction of the Golden Gate Bridge began. Engineer Joseph Strauss designed the bridge, which is the largest suspension bridge in the world as of 2014. The bridge took four years, thousands of workers and $35 million to build. In May 1937, the bridge opened with 18,000 people walking across it. The following day, it was opened to traffic. As of 2014, more than 120,000 cars cross the bridge every day.Learn more about Architecture
The Golden Gate Bridge was built to remedy the need to move people and products in and out of San Francisco via ferry due to the city being located on a peninsula in San Francisco Bay. The city was effectively cut off from areas around it and was being limited in its growth and business potential as it headed into the 20th century.Full Answer >
Viaducts are types of bridges; the term “viaduct” refers to long bridges or series of bridges that are connected to one another or structurally supported by arches or sturdy platforms between two end towers. As with bridges, viaducts may cross waterways or roadways, and exist primarily to provide an overhead passage to move trucks, cars, trains and pedestrians from one point to another.Full Answer >
A truss bridge is the strongest kind of bridge. It combines materials in a simple and efficient way that reduces and spreads out loads over a large area. They flex less than other kinds of bridges and provide greater stability even in extreme weather or traffic.Full Answer >
Videos on bridge building can be found on a number of websites. Ron Hazelton Home Improvement Online (RonHazenton.com) has a video on how to build a wooden foot bridge. The website lays out detailed instructions in several steps, each accompanied by a separate video. The resulting laminated bridge spans 12 feet, rests on heavy block piers and has side rails and decking.Full Answer >