Contra Costa County
| Use attributes for filter ! | |
| Area | 1854 |
|---|---|
| Population | 1. 147 million (2017) |
| County seat | Martinez |
| Points of interest | Mount Diablo |
| Mount Diablo State Park | |
| Date of Reg. | |
| Date of Upd. | |
| ID | 1106766 |
About Contra Costa County
Contra Costa County is a county in the state of California in the United States. As of the 2010 census, the population was 1,049,025. The county seat is Martinez. It occupies the northern portion of the East Bay region of the San Francisco Bay Area, and is primarily suburban.
