page_title: San Francisco Bay
section_title: Transportation
hierarchical_section_title: San Francisco Bay / Transportation
caption_attribution_description: English: Port Of Oakland, California with Oakland Bay Bridge and San Francisco in background.
context_page_description: San Francisco Bay is a shallow estuary in the US state of California. It is surrounded by a contiguous region known as the San Francisco Bay Area, and is dominated by the large cities of San Jose, San Francisco and Oakland.
  San Francisco Bay drains water from approximately 40 percent of California. Water from the Sacramento and San Joaquin rivers, and from the Sierra Nevada mountains, flow into Suisun Bay, which then travels through the Carquinez Strait to meet with the Napa River at the entrance to San Pablo Bay, which connects at its south end to San Francisco Bay. It then connects to the Pacific Ocean via the Golden Gate strait. However, this entire group of interconnected bays is often called the San Francisco Bay. The bay was designated a Ramsar Wetland of International Importance on February 2, 2012.
context_section_description: San Francisco Bay was traversed by watercraft before the arrival of Europeans. Indigenous peoples used canoes to fish and clam along the shoreline. Sailing ships enabled transportation between the Bay and other parts of the world—and served as ferries and freighters within the Bay and between the Bay and inland ports, such as Sacramento and Stockton. These were gradually replaced by steam-powered vessels starting in the late 19th century. Several shipyards were established around the Bay, augmented during wartime. (e.g., the Kaiser Shipyards, Richmond Shipyards) near Richmond in 1940 for World War II for construction of mass-produced, assembly line Liberty and Victory cargo ships.
  San Francisco Bay is spanned by nine bridges, eight of which carry cars.
  The Golden Gate Bridge on U.S. Route 101/State Route 1 (US 101/SR 1) was the largest single span suspension bridge ever built at the time of its 1937 construction. It spans the Golden Gate, the strait between San Francisco and Marin County, and is the only bridge in the area not owned by the State of California.
  The Richmond–San Rafael Bridge on Interstate 580 (I-580) connects Marin and Contra Costa counties.
  The San Francisco–Oakland Bay Bridge on I-80 connects Alameda and San Francisco counties.
  The San Mateo–Hayward Bridge on SR 92 connects Alameda and San Mateo counties.
  The Dumbarton Bridge on SR 84 connects Alameda and San Mateo counties.
  The Carquinez Bridge (including the Alfred Zampa Memorial Bridge) on I-80 connects Contra Costa and Solano counties.
  The Benicia Bridge on I-680 also connects Contra Costa and Solano counties.
  The Antioch Bridge on SR 160 connects Contra Costa and Sacramento counties.
  The Dumbarton Rail Bridge is an abandoned bridge that used to carry rail traffic.
  The Transbay Tube, an underwater rail tunnel, carries BART services between Oakland and San Francisco.
  
  Prior to the bridges and, later, the Transbay Tube, transbay transportation was dominated by fleets of ferryboats operated by the Southern Pacific Railroad and the Key System transit company. However, in recent decades, ferries have returned, primarily serving commuters from Marin County, relieving the traffic bottleneck of the Golden Gate Bridge. (See article Ferries of San Francisco Bay). 
  The bay also continues to serve as a major seaport. The Port of Oakland is one of the largest cargo ports in the United States, while the Port of Richmond and the Port of San Francisco provide smaller services.
caption: Port of Oakland California
exif: {}