The most iconic landmark of Contra Costa County is Mount Diablo, which stands tall at 3,849 feet at the northern end of the Devil's Range. It is the centerpiece of Diablo State Park, one of the many recreational areas that locals and visitors can enjoy. There are no major airports in Contra Costa County with regular passenger service, although there are several general aviation airports. State Route 24, which passes through the Caldecott Tunnel, is the main route to Contra Costa from San Francisco, Oakland and Berkeley.
Democrats have a clear advantage in voter registration numbers in all political subdivisions of Contra Costa County. The county is home to many parks and trails, as well as reservoirs and museum houses managed by the East Bay Regional Park System, the East Bay MUD (the Municipal Public Utilities District %3D of the local water company), areas designated as open space, and Mount Diablo. Between 1836 and 1846, during the time when California was an independent province of Mexico, 15 land concessions were made in Contra Costa County. The racial makeup of Contra Costa County was 614,512 (58.6%) white; 97,161 (9.3%) African American; 6,122 (0.6%) Native Americans; 151,469 (14.4%) Asians (4.6%) from other races (4.6% Filipinos, 3.8% Chinese, 2.1% Indian); 4,845 (0.5%) Pacific Islanders; 112,691 (10.7%) from other races; and 62,225 (5.9%) from two or more races.
Interstate 580 connects Contra Costa to the center of Alameda County to the west and to Stockton and the Central Valley to the east. Contra Costa County is included in the San Francisco—Oakland—Berkeley metropolitan statistical area. Property titles in Contra Costa County can be attributed to multiple subdivisions of some original land grants. Contra Costa County (in Spanish, Opposite Coast) is a county in California located on the east side of San Francisco Bay.
On February 18, 1850, when Contra Costa County was designated as one of California's original twenty-seven counties, it included all of the land in present-day Alameda County. In 1937, the two-hole Caldecott Tunnel for road vehicles was completed, making it easier to access the interior of Contra Costa County. The same hills that keep Contra Costa culturally isolated also protect it from a climate point of view; the area is usually 10 to 20° F (5 to 10° C) warmer than the bay in summer. Before 1903, most trips to downtown Contra Costa County were by boat or rail to Martinez on the north coast and from there to industrial areas in the east along the coast as well as agricultural regions in the south.
The Contra Costa Canal, a fenced irrigation canal lined with concrete, still runs through the center of the county and provides industrial and agricultural water to farms and industry. Since 2003, four Indian gaming casinos have been proposed in Richmond and surrounding areas of western Contra Costa County.