Commonly known as the Bay Area, the San Francisco Bay Area encompasses the major cities and metropolitan areas of San Francisco Oakland, and San Jose and includes nine counties, Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, Solano and Sonoma.

What areas are considered the Bay Area?

“The official definition is the nine county definition,” she says. That's Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, Solano and Sonoma. Among these nine counties are 101 cities, an estimated 7.756 million people and about 7,000 square miles.

What does the Bay Area refer to?

The Bay Area is the urban area surrounding the San Francisco Bay in Northern California. Bay Area may also refer to: Blockhouse Bay, a suburb in Auckland, New Zealand. Greater Tokyo area, an area around Tokyo Bay.