Alameda County 001 Oakland 1853 Contra Costa and Santa Clara The oak and other trees, once abundant in the region; alameda is Spanish for "avenue shaded by trees" or "cottonwood grove". Charter 1,663,190 738 sq mi (1,911 km2) State map highlighting Alameda County Alpine County 003 Markleeville 1864 Amador, El Dorado, Calaveras, Mono and Tuolumne Location high in the Sierra Nevada; alpine refers to the Alps or other mountains. General Law 1,120 739 sq mi (1,914 km2) State map highlighting Alpine County Amador County 005 Jackson 1854 Calaveras Jose Maria Amador (1794.1883), a soldier, rancher, and miner who, along with several Native Americans, established a successful gold mining camp near present-day Amador City in 1848. General Law 38,626 606 sq mi (1,570 km2) State map highlighting Amador County Butte County 007 Oroville 1850 original Sutter Buttes, which were mistakenly thought to be in the county at the time of its establishment. Charter 229,294 1,640 sq mi (4,248 km2) State map highlighting Butte County Calaveras County 009 San Andreas 1850 original Calaveras River; calaveras is Spanish for "skulls". General Law 45,670 1,020 sq mi (2,642 km2) State map highlighting Calaveras County Colusa County 011 Colusa 1850 original Rancho Colus land grant from Mexico. General Law 21,805 1,151 sq mi (2,981 km2) State map highlighting Colusa County Contra Costa County 013 Martinez 1850 original Location across San Francisco Bay from San Francisco; contra costa is Spanish for "opposite coast". General Law 1,147,439 720 sq mi (1,865 km2) State map highlighting Contra Costa County Del Norte County 015 Crescent City 1857 Klamath Location along California's northern border; del norte is Spanish for "northern". General Law 27,470 1,008 sq mi (2,611 km2) State map highlighting Del Norte County El Dorado County 017 Placerville 1850 original El Dorado, a mythical city of gold, owing to the area's significance in the California Gold Rush. Charter 188,987 1,712 sq mi (4,434 km2) State map highlighting El Dorado County Fresno County 019 Fresno 1856 Mariposa, Merced and Tulare The city of Fresno; fresno is Spanish for "ash tree". Charter 989,255 5,963 sq mi (15,444 km2) State map highlighting Fresno County Glenn County 021 Willows 1891 Colusa Dr. Hugh J. Glenn, a California businessman and politician. General Law 28,094 1,315 sq mi (3,406 km2) State map highlighting Glenn County Humboldt County 023 Eureka 1853 Trinity Alexander von Humboldt, a German naturalist and explorer. General Law 136,754 3,573 sq mi (9,254 km2) State map highlighting Humboldt County Imperial County 025 El Centro 1907 San Diego Imperial Valley, named after the Imperial Land Company. General Law 182,830 4,175 sq mi (10,813 km2) State map highlighting Imperial County Inyo County 027 Independence 1866 Mono and Tulare Exact etymology disputed; early settlers believed Inyo to be the native name for area mountains, but it may be the name of a Mono Indian leader. General Law 18,026 10,192 sq mi (26,397 km2) State map highlighting Inyo County Kern County 029 Bakersfield 1866 Los Angeles and Tulare Edward Kern, cartographer for John C. Fremont's 1845 expedition. General Law 893,119 8,142 sq mi (21,088 km2) State map highlighting Kern County Kings County 031 Hanford 1893 Tulare Kings River; original Spanish name Rio de los Santos Reyes ("River of the Holy Kings"). General Law 150,101 1,390 sq mi (3,600 km2) State map highlighting Kings County Lake County 033 Lakeport 1861 Napa Clear Lake. General Law 64,246 1,258 sq mi (3,258 km2) State map highlighting Lake County Lassen County 035 Susanville 1864 Plumas and Shasta, and now defunct Lake County, Nevada Peter Lassen, a Danish naturalist and explorer. General Law 31,163 4,558 sq mi (11,805 km2) State map highlighting Lassen County Los Angeles County 037 Los Angeles 1850 original The city of Los Angeles, derived from the original Spanish name El Pueblo de Nuestra Señ la Reina de los Angeles del Ríde Porciúa ("The Village of Our Lady, the Queen of the Angels of the River of Porziuncola"). Charter 10,163,507 4,060 sq mi (10,515 km2) State map highlighting Los Angeles County Madera County 039 Madera 1893 Mariposa The city of Madera, which was named for the forested landscape; madera is Spanish for "wood". General Law 156,890 2,138 sq mi (5,537 km2) State map highlighting Madera County Marin County 041 San Rafael 1850 original Exact etymology disputed; probably a corrupted abbreviation of Bahíde Nuestra Señ del Rosario la Marina, the Spanish name for area headlands along San Francisco Bay. General Law 260,955 520 sq mi (1,347 km2) State map highlighting Marin County Mariposa County 043 Mariposa 1850 original The city of Mariposa; mariposa is Spanish for "butterfly". General Law 17,569 1,451 sq mi (3,758 km2) State map highlighting Mariposa County Mendocino County 045 Ukiah 1850 original Antonio de Mendoza, first viceroy of New Spain. General Law 88,018 3,509 sq mi (9,088 km2) State map highlighting Mendocino County Merced County 047 Merced 1855 Mariposa The city of Merced, derived from the original Spanish name El Ríde Nuestra Señ de la Merced ("River of Our Lady of Mercy"). General Law 272,673 1,929 sq mi (4,996 km2) State map highlighting Merced County Modoc County 049 Alturas 1874 Siskiyou The Modoc people. General Law 8,859 3,944 sq mi (10,215 km2) State map highlighting Modoc County Mono County 051 Bridgeport 1861 Calaveras, Fresno and Mariposa Mono Lake; derived from Monachi, a Yokut name for native peoples of the Sierra Nevada. General Law 14,168 3,044 sq mi (7,884 km2) State map highlighting Mono County Monterey County 053 Salinas 1850 original Derived from Monterey Bay, which was named for a Viceroy of New Spain, Gaspar de Zú, 5th Count of Monterrey. General Law 437,907 3,322 sq mi (8,604 km2) State map highlighting Monterey County Napa County 055 Napa 1850 original Disputed origin; possibly derived from the Patwin word napo, meaning "home". General Law 140,973 754 sq mi (1,953 km2) State map highlighting Napa County Nevada County 057 Nevada City 1851 Yuba The phrase Sierra Nevada; nevada is Spanish for "snow-covered," referencing the area's high elevation. The neighboring state was named after the county, which was named after Nevada City. General Law 99,814 958 sq mi (2,481 km2) State map highlighting Nevada County Orange County 059 Santa Ana 1889 Los Angeles Oranges, which were widely cultivated in the area at the time the county was established. Charter 3,190,400 948 sq mi (2,455 km2) State map highlighting Orange County Placer County 061 Auburn 1851 Sacramento California Gold Rush, a reference to the area being a center of the California Gold Rush. Charter 386,166 1,407 sq mi (3,644 km2) State map highlighting Placer County Plumas County 063 Quincy 1854 Butte The Feather River; plumas is Spanish for "feathers". General Law 18,742 2,554 sq mi (6,615 km2) State map highlighting Plumas County Riverside County 065 Riverside 1893 San Bernardino and San Diego The city of Riverside, named for its location on the Santa Ana River. General Law 2,423,266 7,208 sq mi (18,669 km2) State map highlighting Riverside County Sacramento County 067 Sacramento 1850 original The city of Sacramento, named after the Santisimo Sacramento (Spanish for "Most Holy Sacrament"). Charter 1,530,615 966 sq mi (2,502 km2) State map highlighting Sacramento County San Benito County 069 Hollister 1874 Monterey Saint Benedict (Benito is a Spanish diminutive of Benedict). General Law 60,310 1,389 sq mi (3,597 km2) State map highlighting San Benito County San Bernardino County 071 San Bernardino 1853 Los Angeles The city of San Bernardino, named after Saint Bernardino of Siena (Spanish for Saint Bernardine). Charter 2,157,404 20,062 sq mi (51,960 km2) State map highlighting San Bernardino County San Diego County 073 San Diego 1850 original The city of San Diego, from Mission San Diego (Spanish for Saint Didacus). Charter 3,337,685 4,204 sq mi (10,888 km2) State map highlighting San Diego County San Francisco 075 San Francisco 1850 original The city of San Francisco, from Presidio of San Francisco and Mission San Francisco de Así named after Saint Francis of Assisi (Spanish for Saint Francis). Charter 884,363 47 sq mi (122 km2) State map highlighting San Francisco San Joaquin County 077 Stockton 1850 original Spanish for Saint Joachim, father of the Virgin Mary. General Law 745,424 1,399 sq mi (3,623 km2) State map highlighting San Joaquin County San Luis Obispo County 079 San Luis Obispo 1850 original The city of San Luis Obispo, from Mission San Luis Obispo, named after Saint Louis of Toulouse (Spanish for Saint Louis, the Bishop). General Law 283,405 3,304 sq mi (8,557 km2) State map highlighting San Luis Obispo County San Mateo County 081 Redwood City 1856 San Francisco and Santa Cruz Spanish for Saint Matthew. Charter 771,410 449 sq mi (1,163 km2) State map highlighting San Mateo County Santa Barbara County 083 Santa Barbara 1850 original The city of Santa Barbara, from Mission Santa Barbara, (Spanish for Saint Barbara). General Law 448,150 2,738 sq mi (7,091 km2) State map highlighting Santa Barbara County Santa Clara County 085 San Jose 1850 original City of Santa Clara, from Mission Santa Clara de Así named for Saint Clare of Assisi (Spanish for Saint Clare). Charter 1,938,153 1,291 sq mi (3,344 km2) State map highlighting Santa Clara County Santa Cruz County 087 Santa Cruz 1850 original The city of Santa Cruz, from Mission Santa Cruz (Spanish for "holy cross"). General Law 275,897 446 sq mi (1,155 km2) State map highlighting Santa Cruz County Shasta County 089 Redding 1850 original Mount Shasta; the indigenous Shasta people. General Law 179,921 3,786 sq mi (9,806 km2) State map highlighting Shasta County Sierra County 091 Downieville 1852 Yuba Sierra is Spanish for "mountain range", a reference to the area's topography. General Law 2,999 953 sq mi (2,468 km2) State map highlighting Sierra County Siskiyou County 093 Yreka 1852 Shasta and Klamath Siskiyou Mountains; exact etymology of Siskiyou is disputed. General Law 43,853 6,287 sq mi (16,283 km2) State map highlighting Siskiyou County Solano County 095 Fairfield 1850 original Chief Solano of the Suisunes. General Law 445,458 828 sq mi (2,145 km2) State map highlighting Solano County Sonoma County 097 Santa Rosa 1850 original Exact etymology disputed; probably a Pomo term meaning "valley of the moon," which references a native legend about spiritual activity in the area. General Law 504,217 1,576 sq mi (4,082 km2) State map highlighting Sonoma County Stanislaus County 099 Modesto 1854 Tuolumne Stanislaus River, named after Estanislao, a native of the area when California was under Spanish and Mexican rule. General Law 547,899 1,495 sq mi (3,872 km2) State map highlighting Stanislaus County Sutter County 101 Yuba City 1850 original John Sutter, a Swiss pioneer of California associated with the California Gold Rush. General Law 96,648 603 sq mi (1,562 km2) State map highlighting Sutter County Tehama County 103 Red Bluff 1856 Butte, Colusa and Shasta The city of Tehama, probably a native term describing its location. Charter 63,926 2,951 sq mi (7,643 km2) State map highlighting Tehama County Trinity County 105 Weaverville 1850 original The city of Trinidad, Spanish for "trinity". General Law 12,709 3,179 sq mi (8,234 km2) State map highlighting Trinity County Tulare County 107 Visalia 1852 Mariposa Tulare Lake, which is named after the tule rush (Schoenoplectus acutus) that grew in the marshes and sloughs along its shores. General Law 464,493 4,824 sq mi (12,494 km2) State map highlighting Tulare County Tuolumne County 109 Sonora 1850 original Exact etymology disputed; probably a corruption of the native term talmalamne, which means "cluster of stone wigwams," a reference to local cave dwelling tribes. General Law 54,248 2,236 sq mi (5,791 km2) State map highlighting Tuolumne County Ventura County 111 Ventura 1872 Santa Barbara The city of Ventura, derived from Mission San Buenaventura (Spanish for St. Bonaventure). General Law 854,223 1,846 sq mi (4,781 km2) State map highlighting Ventura County Yolo County 113 Woodland 1850 original The Yolan people, a local Native American tribe. General Law 219,116 1,012 sq mi (2,621 km2) State map highlighting Yolo County Yuba County 115 Marysville 1850 original Named either by the Maidu people, a local Native American tribe who live on the banks of the Feather and Yuba Rivers, for one of their villages, or by Gabriel Moraga for the wild grapes (Vitis californica) that grow abundantly at the edge of the rivers (uva is Spanish for "grape"). General Law 77,031 630 sq mi (1,632 km2) State map highlighting Yuba County