San Francisco Bay, California, USA37.7N 122.4W
San Francisco Bay is a shallow, productive estuary through which water draining from approximately forty percent of California, USA, flowing in the Sacramento and San Joaquin rivers from the Sierra Nevada mountains, enters the Pacific Ocean.
Technically, both rivers flow into Suisun Bay, which flows 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, although the entire group of interconnected bays are often referred to as “San Francisco Bay.”
The Bay covers somewhere between 400 and 1,600 square miles (1,040 to 4,160 square kilometers), depending on which sub-bays (such as San Pablo Bay), estuaries, wetlands, and so on are included in the measurement.
Here, the waters in the bay and sub-bays is tan from sediments. Further inland, the tan, silt-laden rivers stand out easily against the green and brown of the surrounding landscape.
The main part of the Bay measures 3 to 12 miles (5 to 20 km) wide east-to-west and somewhere between 48 miles (77 km) and 60 miles (97 km) north-to-south.