San Francisco Bay is a shallow estuary in the U.S. state of California. It is surrounded by a contiguous region known as the San Francisco Bay Area (often simply "the Bay Area"), and is dominated by the large cities San Francisco, Oakland, and San Jose.
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. The Guadalupe River enters the bay at it southern most point in San Jose. The Guadalupe drains water from the Santa Cruz mountains and Hamilton Mountain ranges in southern most San Jose. It enters the bay at the town of Alviso. 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.
read more show less