The original bridge, known as the San Francisco Bay Toll-Bridge, opened in 1929 and was then the longest bridge in the world. The original bridge was mostly a two-lane causeway with a 300-foot (91 m) vertical lift span over the main shipping channel. The bridge originally had pole lights along the entire stretch, which were later abandoned except over the vertical lift span. It was replaced with a modern span in 1967. The total length of the bridge is 7 miles (11.3 km). The 1.9-mile (3.1 km) highrise section, the western end of the bridge, is composed of multiple steel girder spans. The eastern trestle portion accounts for the remaining 5.1 miles (8.2 km) of the overall length. The shipping channel beneath the highrise is 750 feet (229 m) wide with a vertical clearance of 135 feet (41 m). The bridge underwent an extensive seismic retrofitting to protect against earthquake damage, with work being completed in 2000. The bridge carries about 93,000 cars and other vehicles on a typical day.
The highrise section was initially built with six lanes and the eastern causeway with four lanes (two in each direction). The causeway section was a perennial traffic bottleneck until it was expanded to six lanes in 2003, along with much needed improvements in its connections with Interstate 880 in Hayward.
High-voltage power lines built by PG&E parallel the bridge all the way across the bay. They provide power to the peninsula and San Francisco.
The bridge was considered the worst evening commute in the Bay Area, which ended with the completion of the bridge's widening in January 2003. Funded as part of BATA's RM 1 program, the low-rise trestle portion of the bridge was widened by Caltrans from four to six lanes to match the configuration of the high-rise portion of the bridge.
Tolls are only collected from westbound traffic at the toll plaza on the east side of the bridge. Since July 2010, the toll rate for passenger cars is $5. Drivers may either pay by cash or use the FasTrak electronic toll collection device. During peak traffic hours, the two left lanes are designated HOV lanes, allowing carpool vehicles carrying two or more people or motorcycles to pass for a toll of $2.50. The next three lanes are FasTrak-only lanes. During non-peak hours the two HOV lanes become FasTrak-only lanes.