San Francisco Bay Area

The San Francisco Bay Area, sometimes referred to as The Bay Area, is a metropolitan area that lies along the San Francisco Bay in northern California. It is often defined as the area covered by the nine counties that border either San Francisco Bay or San Pablo Bay: Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, Solano, and Sonoma. By this definition, the Bay Area has a population of over seven million residents. Santa Cruz County is sometimes considered a member of the Bay Area as well. It does not adjoin the San Francisco Bay, but has strong cultural ties to the Bay Area.

This nine- or ten-county area consists of cities of various size that lie more or less contiguously around the length of the bay. Three large cities dominate the area: San Francisco, San Jose, and Oakland. Because, unlike most other metropolitan areas in the United States, no single large city dominates the region, residents generally refer to the region generically as the Bay Area, without associating it with any one city. However, because San Francisco was historically the first major population center in the area, and because of its densely urbanized character in constrast to its neighbors, people in the region often refer to San Francisco as simply the City.

A more restrictive, informal definition includes only the urban portions of the previously defined area and also excludes Napa, Solano, and Sonoma counties, which are largely rural or suburban in character and have inland climates. The Bay Area Rapid Transit District consists of Alameda, Contra Costa, and San Francisco Counties. High real-estate prices in this core of the Bay Area have driven many residents and businesses to move to outlying areas or to the Sacramento area. As this trend continues, the definition of the Bay Area will likely expand, perhaps even including Yolo County as well.

Map of the San Francisco Bay Area

Table of contents

1 Geography
2 Subregions
3 List of Counties
4 Anchor Cities
5 Suburbs with more than 100,000 inhabitants
6 Suburbs with 10,000 to 100,000 inhabitants
7 Suburbs with less than 10,000 inhabitants
8 Related articles

Geography

The combined area of the nine Bay Area counties is 22,789 km² (8,798 mi²), or 21,216 km² (8,191 mi²), not including Santa Cruz County.

As well as constituting one of the world's greatest metropolitan areas, the Bay Area includes some exceptional natural coastal and rural landscape. It includes significant national parks such as the Point Reyes National Seashore, a large number of state parks including important ones like the Mount Diablo State Park, and numerous parks and preserves maintained by local government agencies - notably by the East Bay Regional Park District which has major land holdings in Alameda and Contra Costa counties. Most of these conserved areas are within easy reach of the metropolitan areas, many of them by public transportation.

Because the hills, mountains, and large bodies of water produce such vast geographic diversity within this region, the Bay Area offers a signficant variety of microclimates. The areas near the Pacific Ocean are generally characterized by relatively small temperature variations during the year, with cool foggy summers and mild rainy winters. Inland areas, especially those separated from the ocean by hills or mountains, have hotter summers and colder overnight temperatures during the winter.

Subregions

The population distribution of the Bay Area is generally subdivided into several smaller subregions.

The region north of the Golden Gate Bridge is known as the North Bay. This area consists of Marin County and extends northward into the Napa and Sonoma Valley wine regions. With some exceptions, this region is relatively affluent, and is generally the least urbanized part of the Bay Area, with many areas of undeveloped park and farm land. It is the only section of the Bay Area that is not served by a commuter rail transit service.
The eastern side of the bay, dominated by the city of Oakland but also including Berkeley, Richmond and several small cities, is known as the East Bay. The region, partly thanks to the Bay Area Rapid Transit (BART) rail service, has extended beyond the East Bay hills into suburban communities such as Walnut Creek, Concord and Antioch. The weather on the eastern side of the hills is markedly warmer in the summer, but gets much cooler than San Francisco, which tends to maintain a rather moderate climate year-round.
The communities along the southern edge of the Bay, synonymous with Silicon Valley, are also known as the South Bay. It includes the cities of San Jose, Fremont, and the high-tech hub of Santa Clara, as well as many smaller communities.
The area between the South Bay and the city of San Francisco is known as the San Francisco Peninsula, locally just as The Peninsula. This area consists of a series of small cities and suburban communities along the Bay, as well as various towns along the Pacific coast.
San Francisco is generally placed in a category by itself, separated by water from the north and east, and by county line from its neighbor cities to the South (Daly City, South San Francisco and Brisbane).

List of Counties

Anchor Cities

Oakland (Major Airport: Oakland International Airport)
San Francisco (Major Airport: San Francisco International Airport
San Jose (Major Airport: San Jose International Airport)

Suburbs with more than 100,000 inhabitants

Suburbs with 10,000 to 100,000 inhabitants

Suburbs with less than 10,000 inhabitants

Geography of California