February 18, 1850
4.8% (Apr 2015)
6,536 ft (1,992 m)
3.211 million (2013)
United States of America
Pacific Time Zone (UTC-8)
Points of interest
Balboa Park, San Diego Zoo Safari Park
Tijuana River, Santa Margarita River, Olla Wash
San Diego, Anza‑Borrego Desert St, Carlsbad, Coronado, Oceanside
Colleges and Universities
University of California, San Diego State University, University of San Diego, California State University, Palomar College
San Diego County is a county in the southwestern corner of the state of California, in the United States. As of the 2010 census, the population was 3,095,313. making it California's second-most populous county and the fifth-most populous in the United States. Its county seat is San Diego, the eighth-most populous city in the United States. It is the south-westernmost county in the 48 contiguous United States.
- Map of San Diego County CA USA
- National protected areas
- Other demographics
- Federal and state representation
- US Navy
- US Marine Corps
- US Coast Guard
- Sites of interest
- Other media
- Border crossings to Mexico
- Light rail and local transit
- The Port of San Diego
- Indian reservations
- Population ranking
Map of San Diego County, CA, USA
San Diego County comprises the San Diego-Carlsbad Metropolitan Statistical Area. The San Diego-Carlsbad, CA Metropolitan Statistical Area is the 17th most populous metropolitan statistical area and the 18th most populous primary statistical area of the United States as of July 1, 2012. San Diego is also part of the San Diego–Tijuana metropolitan area, the largest metropolitan area shared between the United States and Mexico. Greater San Diego ranks as the 38th largest metropolitan area in the Americas.
San Diego County has 70 miles (110 km) of coastline. Most of the county has a mild Mediterranean climate to semiarid climate, though there are mountains that receive frost and snow in the wintertime.
There are also 16 naval and military installations of the U.S. Navy, U.S. Marine Corps, and the U.S. Coast Guard in San Diego County. These include the Naval Base San Diego, Marine Corps Base Camp Pendleton, Marine Corps Air Station Miramar, and Naval Air Station North Island.
From north to south, San Diego County extends from the southern borders of Orange County and Riverside County to the Mexico–United States border and Baja California. From west to east, San Diego County stretches from the Pacific Ocean to its boundary with Imperial County.
The area which is now San Diego County has been inhabited for more than 10,000 years by Kumeyaay (also called Diegueño), Luiseño, Cupeño and Cahuilla Indians.
In 1542, the Portuguese-born explorer Juan Rodríguez Cabrillo, sailing for Spain, claimed San Diego Bay for the Spanish Empire, and he named the site San Miguel. In November 1602, Sebastián Vizcaíno surveyed the harbor and what are now Mission Bay and Point Loma and named the area for Saint Didacus, a Spaniard more commonly known as San Diego. European settlement in what is now San Diego County began with the founding of the San Diego Presidio and Mission San Diego de Alcalá by Spanish soldiers and clerics in 1769. This county was part of Alta California under the Viceroyalty of New Spain until the Mexican declaration of independence. From 1821 through 1848 this area was part of Mexico.
San Diego County became part of the United States as a result of the Treaty of Guadalupe Hidalgo in 1848, ending the U.S.-Mexican War. This treaty designated the new border as terminating at a point on the Pacific Ocean coast which would result in the border passing one Spanish league south of the southernmost portion of San Diego Bay, thus ensuring that the United States received all of this natural harbor.
San Diego County was one of the original counties of California, and it was created at the time of California statehood in 1850.
At the time of its establishment in 1850, San Diego County was relatively large, and included all of southernmost California which was south and east of Los Angeles County. As such it included areas of what are now Inyo County and San Bernardino County, as well as all of what is now Riverside County and Imperial County.
During the later part of the 19th century, there were numerous changes in the boundaries of San Diego County, when various areas became separated for the counties mentioned above. The most recent changes were the establishments of Riverside County in 1893 and Imperial County in 1907. Imperial County was also the last county to be established in California, and after this division, San Diego no longer extended from the Pacific Ocean to the Colorado River, and it no longer covered the entire border between California and Mexico.
According to the U.S. Census Bureau, the county has an area of 4,526 square miles (11,720 km2), of which 4,207 square miles (10,900 km2) is land and 319 square miles (830 km2) (7.0%) is water. The county is larger in area than the combined states of Rhode Island and Delaware.
San Diego County has a varied topography. On its western side is 70 miles (110 km) of coastline. Most of San Diego between the coast and the Laguna Mountains consists of hills, mesas, and small canyons. Snow-capped (in winter) mountains rise to the northeast, with the Sonoran Desert to the far east. Cleveland National Forest is spread across the central portion of the county, while the Anza-Borrego Desert State Park occupies most of the northeast.
Although the county's western third is primarily urban, the mountains and deserts in the eastern two-thirds are primarily of undeveloped backcountry. Most of these backcountry areas are home to a native plant community known as chaparral. San Diego County contains more than a million acres (4,000 km²) of chaparral, twice as much as any other California county.
North San Diego County is known as North County; the exact geographic definitions of "North County" vary, but it includes the northern suburbs and sometimes certain northern neighborhoods of the City of San Diego.
The eastern suburbs are collectively known as East County, though most still lie in the western third of the county. The southern suburbs and southern detached portion of the city of San Diego, extending to the Mexican border, are collectively referred to as South Bay.
Periodically the area has been subject to wildfires that force thousands to evacuate. The most recent are the May 2014 San Diego County wildfires; before them was the Witch Creek Fire in 2007 and the Cedar Fire in 2003. California defines a fire season in which fires are most likely to occur, usually between late July and late October (which are the driest months of the area). Signs posted in numerous spots of the county provide information on the level of threats from fires based on weather conditions.
Under the Köppen climate classification system, the San Diego area straddles areas of Mediterranean climate (CSa) to the north and semi-arid climate (BSh) to the south and east. As a result, it is often described as "arid Mediterranean" and "semi-arid steppe". San Diego's climate is characterized by warm, dry summers and mild winters with most of the annual precipitation falling between November and March. The city has mild, mostly dry weather, with an average of 201 days above 70 °F (21 °C) and low rainfall (9–13 inches (23–33 cm) annually). Summer temperatures are generally warm, with average highs of 70–78 °F (21–26 °C) and lows of 55–66 °F (13–19 °C). Temperatures exceed 90 °F (32 °C) only four days a year. Most rainfall occurs from November to April. Winter temperatures are mild, with average high temperatures of 66–70 °F (19–21 °C) and lows of 50–56 °F (10–13 °C).
The climate in the San Diego area, like much of California, often varies significantly over short geographical distances resulting in microclimates. In San Diego's case this is mainly due to the city's topography (the Bay, and the numerous hills, mountains, and canyons). Frequently, particularly during the "May gray/June gloom" period, a thick marine layer will keep the air cool and damp within a few miles of the coast, but will yield to bright cloudless sunshine approximately 5–10 miles (8.0–16.1 km) inland. This happens every year in May and June. Even in the absence of June gloom, inland areas tend to experience much more significant temperature variations than coastal areas, where the ocean serves as a moderating influence. Thus, for example, downtown San Diego averages January lows of 50 °F (10 °C) and August highs of 78 °F (26 °C). The city of El Cajon, just 10 miles (16 km) northeast of downtown San Diego, averages January lows of 42 °F (6 °C) and August highs of 88 °F (31 °C).
Rainfall along the coast averages about 10 inches (25 cm) of precipitation annually, which occurs mainly during the cooler months of December through April. Though there are few wet days per month during the rainy period, rainfall can be heavy when it does occur. However, the rainfall is greater in the higher elevations of San Diego. Some of the higher areas of San Diego can receive 11–13 inches (28–33 cm) of rain a year.
National protected areas
There are 7 official wilderness areas in San Diego County that are part of the National Wilderness Preservation System. Four of these are integral parts of Cleveland National Forest, whereas three are managed by the Bureau of Land Management. Some of these extend into neighboring counties (as indicated below):
There are 236 mountain summits and peaks in San Diego County including:
Half of the county's population lives in San Diego and Chula Vista. In 2000, only about 3% of San Diego County residents left the county for work while 40,000 people commuted into the metropolitan area.
The 2010 United States Census reported that San Diego County had a population of 3,095,313. The racial makeup of San Diego County was 1,981,442 (64.0%) White, 158,213 (5.1%) African American, 26,340 (0.9%) Native American, 336,091 (10.9%) Asian (4.7% Filipino, 1.6% Chinese, 1.4% Vietnamese, 3.2% Other Asian), 15,337 (0.5%) Pacific Islander, 419,465 (13.6%) from other races, and 158,425 (5.0%) from two or more races. Hispanic or Latino of any race were 991,348 persons (32.0%).
As of 2009, the racial makeup of the county was 79.4% White American, 5.6% Black or African American, 1% Native American, 10.4% Asian, 0.5% Pacific Islander, 10.3% from other races, and 3.6% from two or more races. 31.3% of the population were Hispanic or Latino of any race.
67.0% spoke only English at home; 21.9% spoke Spanish, 3.1% Tagalog and 1.2% Vietnamese.
As of 2009 Census Bureau estimates, there were 3,053,793 people, 1,067,846 households, and 663,449 families residing in the county. The population density was 670 people per square mile (259/km²). There were 1,142,245 housing units at an average density of 248 per square mile (96/km²).
In 2000 there were 994,677 households out of which 33.9% had children under the age of 18 living with them, 50.7% were married couples living together, 11.6% had a female householder with no husband present, and 33.3% were non-families. 24.2% of all households were made up of individuals and 7.9% had someone living alone who was 65 years of age or older. The average household size was 2.73 and the average family size was 3.29.
As of 2000, in the county the population was spread out with 25.7% under the age of 18, 11.30% from 18 to 24, 32.0% from 25 to 44, 19.8% from 45 to 64, and 11.2% who were 65 years of age or older. The median age was 33 years. For every 100 females there were 101.2 males. For every 100 females age 18 and over, there were 99.7 males.
According to the 2000 Census, the median income for a household in the county was $47,067, and the median income for a family was $53,438. Males had a median income of $36,952 versus $30,356 for females. The per capita income for the county was $22,926. About 8.9% of families and 12.4% of the population were below the poverty line, including 16.5% of those under age 18 and 6.8% of those age 65 or over.
Much of the county's high-income residents are concentrated in the northern part of the city of San Diego. The San Diego metropolitan area has two places with both a population of over 50,000 and a per capita income of over $40,000: Carlsbad and Encinitas.
The county's largest continuous high-income urban area is a triangle from a first point on the northern edge of Carlsbad, a second point southeast of Escondido, and a third point on the southern edge of La Jolla. It contains all or most of the cities of Carlsbad, Encinitas, Solana Beach, Del Mar, and Poway in addition to a substantial portion of northern San Diego.
The Government of San Diego County is defined and authorized under the California Constitution, California law, and the Charter of the County of San Diego. Much of the Government of California is in practice the responsibility of county governments such as the Government of San Diego County. The County government provides countywide services such as elections and voter registration, law enforcement, jails, vital records, property records, tax collection, public health, and social services. In addition the County serves as the local government for all unincorporated areas. Some chartered cities such as San Diego and Chula Vista provide municipal services such as police, public safety, libraries, parks and recreation, and zoning. Other cities such as Del Mar and Vista arrange to have the County provide some or all of these services on a contract basis.
The county government is composed of the elected five-member Board of Supervisors, several other elected offices and officers including the Sheriff, the District Attorney, Assessor/Recorder/County Clerk, and Treasurer/Tax Collector, and numerous county departments and entities under the supervision of the Chief Administrative Officer such as the Probation Department. In addition, several entities of the government of California have jurisdiction conterminous with San Diego County, such as the San Diego Superior Court.
Under its foundational Charter, the five-member elected San Diego County Board of Supervisors is the county legislature. The board operates in a legislative, executive, and quasi-judicial capacity. As a legislative authority, it can pass ordinances for the unincorporated areas (ordinances that affect the whole county, like posting of restaurant ratings, must be ratified by the individual city). As an executive body, it can tell the county departments what to do, and how to do it. As a quasi-judicial body, the Board is the final venue of appeal in the local planning process.
As of January 2013 the members of the San Diego County Board of Supervisors are:
For several decades, ending in 2013, all five supervisors were Republican, white, graduates of San Diego State University, and had been in office since 1995 or earlier. The Board was criticized for this homogeneity, which was made possible because supervisors draw their own district lines and are not subject to term limits. (In 2010 voters put term limits in place, but they only apply going forward, so that each incumbent supervisor can serve an additional two terms before being termed out.) That pattern was broken in 2013 when Slater-Price retired; she was replaced by Democrat Dave Roberts, who won election to the seat in November 2012 and was inaugurated in January 2013.
The San Diego County Code is the codified law of San Diego County in the form of ordinances passed by the Board of Supervisors. The Administrative Code establishes the powers and duties of all officers and the procedures and rules of operation of all departments.
The county motto is "The noblest motive is the public good." County government offices are housed in the historic County Administration Center Building, constructed in 1935-1938 with funding from the Works Progress Administration.
As of June 2013, there are 1,556,739 registered voters in San Diego County. Of those, 547,897 (35.2%) are registered Democratic, 526,306 (33.8%) are registered Republican, 401,340 (25.8%) declined to state a political party, 51,993 (3.3%) are registered American Independence Party, 11,657 (0.7%) are registered Libertarian, 7,675 (0.5%) are registered Green, and 4,012 (0.3%) are registered Peace & Freedom.
San Diego County has historically been a Republican stronghold. The Republican presidential nominee carried the county in every presidential election from 1948 through 2004, except in 1992 when Bill Clinton won a plurality. In 2008, Barack Obama became the first Democratic presidential candidate to win a majority of votes in San Diego County since World War II; he won a majority of county votes again in 2012. In 2016, the county voted in favor of the Democratic presidential nominee Hillary Clinton by the largest margins for a democrat since 1936.
The city of San Diego itself is more Democratic than the county's average and has voted for Democrats in each presidential election since 1992. Various cities within the county are swing areas that have split their votes in elections since 2000. Republican strength is concentrated in North County, as well as the inland portions.
One unique feature of the political scene is the use of Golden Hall, a convention facility next to San Diego's City Hall, as "Election Central." The County Registrar of Voters rents the hall to distribute election results. Supporters and political observers gather to watch the results come in; supporters of the various candidates parade around the hall, carrying signs and chanting; candidates give their victory and concession speeches and host parties for campaign volunteers and donors at the site; and television stations broadcast live from the floor of the convention center. The atmosphere at Election Central on the evening of election day has been compared to the voting portion of a political party national convention.
On Nov 4, 2008 San Diego County voted 53.8% for Proposition 8 which amended the California Constitution to ban same-sex marriages, thus restoring Proposition 22 which was overturned by a ruling from the California Supreme Court. However the city of San Diego, along with Del Mar, Encinitas, and Solana Beach, voted against Proposition 8.
Federal and state representation
In the U.S. House of Representatives, San Diego County is split between five congressional districts:
In the California State Assembly, San Diego County is split between seven legislative districts:
In the California State Senate, San Diego County is split between four legislative districts:
The following table includes the number of incidents reported and the rate per 1,000 persons for each type of offense.
Arising from an effort by the state government to identify regional economies, San Diego County and Imperial County are part of the Southern Border Region, one of nine such regions. As a regional economy, the Southern Border Region is the smallest but most economically diverse region in the state. However, the two counties maintain weak relations and have little in common aside from their common border.
San Diego County's agriculture industry was worth $1.85 billion in 2013, and is one of the top five egg producing counties in the United States. In 2013, San Diego County also had the most small farms of any county in the United States, and had the 19th largest agricultural economy of any county in the United States. According to the San Diego Farm Bureau, San Diego County is the United States leading producer of avocados, and nursery crops.
Tourism plays a large part in the economics of the San Diego metropolitan area. Tourists are drawn to the region for a well rounded experience, everything from shopping to surfing as well as its mild climate. Its numerous tourist destinations include Horton Plaza, Westfield UTC, Seaport Village, Westfield Mission Valley and Fashion Valley Mall for shopping. SeaWorld San Diego and Legoland California as amusement parks. Golf courses such as Torrey Pines Golf Course and Balboa Park Golf Course. Museums such as the San Diego Museum of Man, San Diego Museum of Art, Reuben H. Fleet Science Center, San Diego Natural History Museum, USS Midway Museum, and the San Diego Air and Space Museum. Historical places such as the Gaslamp Quarter, Balboa Park and Old Town San Diego State Historic Park. Wildlife refuges, zoos, and aquariums such as the Birch Aquarium at Scripps, San Diego Zoo's Safari Park, San Diego Zoo and San Diego-La Jolla Underwater Park. Outdoor destinations include the Peninsular Ranges for hiking, biking, mountainboarding and trail riding. Surfing locations include Swami's, Stone Steps Beach, Torrey Pines State Beach, Cardiff State Beach, San Onofre State Beach and the southern portion of Black's Beach.
The region is host to the second largest cruise ship industry in California which generates an estimated $2 million annually from purchases of food, fuel, supplies, and maintenance services. In 2008 the Port of San Diego hosted 252 ship calls and more than 800,000 passengers.
San Diego County contains three public state universities: University of California, San Diego; San Diego State University; and California State University, San Marcos. Major private universities in the county include University of San Diego (USD), Point Loma Nazarene University (PLNU), Alliant International University (AIU), and National University. It also includes three law schools, USD School of Law, California Western School of Law, and Thomas Jefferson School of Law
Within the county there are 24 public elementary school districts, 6 high school districts, and 12 unified school districts. There are also 5 community college districts.
There are two separate public library systems in San Diego County: the San Diego Public Library serving the city of San Diego, and the San Diego County Library serving all other areas of the county. In 2010 the county library had 33 branches and two bookmobiles; circulated over 10.7 million books, CDs, DVDs, and other material formats; recorded 5.7 million visits to library branches; and hosted 21,132 free programs and events. The San Diego County Library is one of the 25 busiest libraries in the nation as measured by materials circulated.
San Diego is the headquarters of the U.S. Navy's Eleventh Naval District and is the Navy's principal location for West Coast and Pacific Ocean operations. Naval Base San Diego, California is principal home to the Pacific Fleet (although the headquarters is located in Pearl Harbor). NAS North Island is located on the north side of Coronado, and is home to Headquarters for Naval Air Forces and Naval Air Force Pacific, the bulk of the Pacific Fleet's helicopter squadrons, and part of the West Coast aircraft carrier fleet.
The Naval Special Warfare Center is the primary training center for SEALs, and is also located on Coronado. The area contains five major naval bases and the U.S. Marines base Camp Pendleton. Marine Corps Base Camp Pendleton is the major West Coast base of the United States Marine Corps and serves as its prime amphibious training base. It is located on the Southern California coast, bordered by Oceanside to the south, San Clemente to the north, and Fallbrook to the east.
U.S. Marine Corps
U.S. Coast Guard
The culture of San Diego is influenced heavily by American and Mexican cultures due to its position as a border town, its large Hispanic population, and its history as part of Spanish America and Mexico. The area's longtime association with the U.S. military also contributes to its culture. Present-day culture includes many historical and tourist attractions, a thriving musical and theatrical scene, numerous notable special events, a varied cuisine, and a reputation as one of America's premier centers of craft brewing.
The most popular sports team in the San Diego metropolitan area is a major professional sports teams — the MLB's Padres — and the college sports teams of the San Diego State Aztecs. The following table shows all sports teams in the San Diego metropolitan area that average over 8,000 fans per game:
Sites of interest
San Diego County is served by many newspapers. The major regional paper is The San Diego Union-Tribune, also known as U-T San Diego, is ranked 23rd in the country (by daily circulation) as of March 2013. The Union-Tribune serves both San Diego County and neighboring Imperial County. The former North County Times, based in Escondido and serving portions of Riverside County and North County, was purchased by the Union-Tribune in 2012 and closed down. For about a year after absorbing the North County Times the Union-Tribune published a North County edition, but the regional edition was later abandoned. The Los Angeles Times is also delivered in portions of the county. Many of the area's cities, towns and neighborhoods have their own local newspapers; the Union Tribune bought eight local weeklies in 2013 and is continuing to publish them as independent local newspapers. The San Diego Daily Transcript reports business and legal news. Privately published papers like the Military Press Newspaper and the Navy Dispatch serve the military community both on and off base.
County Television Network is a public-access television cable channel, offering a "hometown blend of C-SPAN, the Lifetime, History, Travel, and Discovery channels" for the county, and funded by fees paid by cable companies.
Border crossings to Mexico
Light rail and local transit
The Port of San Diego
San Diego County has 18 federally recognized Indian reservations, more than any other county in the United States. Although they are typical in size to other Indian reservations in California (many of which are termed "Rancherías"), they are relatively tiny by national standards, and all together total 200.2 square miles (518.5 km²) of area.
The population ranking of the following table is based on the 2010 census of San Diego County.
† county seat