San Francisco-Oakland Bay Bridge

San Francisco-Oakland Bay Bridge, series of connected suspension bridges that join Oakland, California to Buena Yerba Island and Buena Yerba Island to San Francisco. Over 8 mi (13 km) long, it is one of the longest constructed spans over water in the world. Each part of the full span consists of a 2-tiered suspension bridge. In addition, a tunnel and a viaduct lead to Oakland. The earthquake of 1989 collapsed part of the bridge, built in the 1930s.