Contra Costa County | |
|---|---|
.jpg)  Images, from left to right: Contra Costa County courthouse, Mount Diablo's North Peak | |
 Seal  Coat of arms | |
 Interactive map of Contra Costa County | |
 Location in the state of California | |
| Country | United States |
| State | California |
| Region | San Francisco Bay Area |
| Incorporated | February 18, 1850[1] |
| Named for | "Opposite coast" (Spanish: Contra costa) of the San Francisco Bay |
| County seat | Martinez |
| Largest city | Concord (population and land area) Richmond (total area) |
| Government | |
| • Type | Council–CAO |
| • Body | Board of Supervisors |
| • Chair | John Gioia |
| • Vice Chair | Federal D. Glover |
| • Board of Supervisors[2] | Supervisors
|
| • County Administrator Office[3] | Monica Nino |
| Area | |
• Total | 804 sq mi (2,080 km2) |
| • Land | 715.94 sq mi (1,854.3 km2) |
| • Water | 81 sq mi (210 km2) |
| Highest elevation | 3,852 ft (1,174 m) |
| Population (2020) | |
• Total | 1,165,927 |
• Estimate (2023) | 1,155,025  |
| • Density | 1,500/sq mi (560/km2) |
| GDP | |
| • Total | $94.802 billion (2022) |
| Time zone | UTC−8 (Pacific Time Zone) |
| • Summer (DST) | UTC−7 (Pacific Daylight Time) |
| Area code | 510, 341, 925 |
| FIPS code | 06-013 |
| GNIS feature ID | 1675903 |
| Congressional districts | 8th, 9th, 10th |
| Website | contracosta |
Contra Costa County (/ˌkɒntrə ˈkɒstə/ ; Contra Costa, Spanish for 'Opposite Coast') is a county located in the U.S. state of California, in the East Bay of the San Francisco Bay Area. As of the 2020 United States Census, the population was 1,165,927.[6] The county seat is Martinez.[7][8] It occupies the northern portion of the East Bay region of the San Francisco Bay Area and is primarily suburban. The county's name refers to its position on the other side of the bay from San Francisco.[9] Contra Costa County is included in the San Francisco–Oakland–Berkeley, CA Metropolitan Statistical Area.
- ^ "Chronology". California State Association of Counties. Archived from the original on January 29, 2016. Retrieved February 6, 2015.
- ^ "District Offices | Contra Costa County, CA Official Website".
- ^ "County Administrator's Office | Contra Costa County, CA Official Website".
- ^ "Mount Diablo". Peakbagger.com. Archived from the original on May 2, 2015. Retrieved February 6, 2015.
- ^ "Gross Domestic Product: All Industries in Contra Costa County, CA". fred.stlouisfed.org.
- ^ "Contra Costa County, California". United States Census Bureau. Retrieved January 30, 2022.
- ^ "Contra Costa County, California Official Website". Archived from the original on June 18, 2018. Retrieved January 24, 2009.
- ^ "Find a County". National Association of Counties. Archived from the original on May 31, 2011. Retrieved June 7, 2011.
- ^ "Contra Costa County, California Official Website - Visiting". Archived from the original on February 27, 2009. Retrieved January 24, 2009.