San Mateo County

San Mateo County, California
County
County of San Mateo
Images, from top down, left to right: A view of San Francisco Bay from the San Francisco Bay Discovery Site, Port of Redwood City, San Bruno Mountain State Park, the historic Filoli Mansion, South San Francisco Hillside Sign, Montara State Beach
Seal
Motto: All of California in One County
Location in the state of California
California's location in the United States
Coordinates: 37°26′N 122°22′W / 37.44°N 122.36°W / 37.44; -122.36Coordinates: 37°26′N 122°22′W / 37.44°N 122.36°W / 37.44; -122.36
Country	United States
State	California
Region	San Francisco Bay Area
Incorporated	19 April 1856
Named for	Saint Matthew (English translation)
County seat	Redwood City
Largest city	Daly City (population) Redwood City (area)
Area
• Total	744 sq mi (1,930 km2)
• Land	448 sq mi (1,160 km2)
• Water	293 sq mi (760 km2)
Highest elevation	2,603 ft (793 m)
Population (April 1, 2010)
• Total	718,451
• Estimate (2015)	765,135
• Density	1,693/sq mi (654/km2)
Time zone	Pacific Time Zone (UTC-8)
• Summer (DST)	Pacific Daylight Time (UTC-7)
Area codes	415/628, 650
FIPS code	06-081
GNIS feature ID	277305
Website	www.smcgov.org

San Mateo County (/ˌsæn məˈteɪ.oʊ/ SAN mə-TAY-oh; Spanish for "Saint Matthew") is a county located in the U.S. state of California. As of the 2010 census, the population was 718,451. The county seat is Redwood City.

San Mateo County is included in the San Francisco-Oakland-Hayward, CA Metropolitan Statistical Area, and is part of the San Francisco Bay Area, the nine counties bordering San Francisco Bay. It covers most of the San Francisco Peninsula. San Francisco International Airport is located at the northern end of the county, and Silicon Valley begins at the southern end. The county's built-up areas are mostly suburban with some areas being very urban, and are home to several corporate campuses.