Walnut Creek

Walnut Creek, residential city, Contra Costa County, western California, near Oakland; settled 1849, incorporated 1914. Some manufacturing and research industries are here; Mount Diablo State Park is nearby. The community, named for its many walnut trees, was a small farm center until commuter rail service to Oakland was begun in the early 20th century. Population 53,643 (1980); 60,569 (1990); 64,296 (2000); 63,701 (2006).