Southern California (commonly shortened to SoCal) is a geographic and cultural region that generally comprises the southern portion of the U.S. state of California. Its densely populated coastal region includes Greater Los Angeles (the second-most populous urban agglomeration in the United States)^[4][5] and San Diego County (the second-most populous county in California). The region generally contains ten of California's 58 counties: Los Angeles, San Diego, Orange, Riverside, San Bernardino, Kern, Ventura, Santa Barbara, San Luis Obispo, and Imperial counties.

Although geographically smaller than Northern California in land area, Southern California has a higher population, with 23.76 million residents as of the 2020 census. The sparsely populated desert region of California occupies a significant portion (part of which has even been proposed to be split into a new county due to cultural, economic and geographic differences relative to the rest of the more urban region) of the area: the Colorado Desert, along with the Colorado River, is located on Southern California's eastern border with Arizona, and the Mojave Desert shares a border with Nevada to the northeast. Southern California's southern border with Baja California is part of the Mexico–United States border.

Southern California encompasses eight metropolitan areas (MSAs), three of which together form the Greater Los Angeles Combined Statistical Area (CSA) with over 18 million people, the second-biggest CSA after the New York CSA. These three MSAs are the Los Angeles metropolitan area (Los Angeles and Orange counties, with 13.3 million people), the Inland Empire (Riverside and San Bernardino counties, including the Coachella Valley cities, with 4.3 million people), and the Oxnard–Thousand Oaks–Ventura metropolitan area (0.8 million people). In addition, Southern California contains the San Diego metropolitan area with 3.3 million people, Bakersfield metro area with 0.9 million, and the Santa Barbara, San Luis Obispo, and El Centro (Imperial County) metropolitan areas.

The Southern California Megaregion (or megalopolis) is larger still, extending northeast into Las Vegas, Nevada and south across the Mexican border into Tijuana.^[6]

Within Southern California are two major cities, Los Angeles and San Diego, as well as three of the country's largest metropolitan areas.^[7] With a population of approximately 4 million, Los Angeles is the most populous city in California and the second most populous in the United States. South of Los Angeles and with a population of approximately 1.4 million is San Diego, the second most populous city in the state and the eighth most populous in the nation.

The counties of Los Angeles, San Diego, Orange, Riverside, and San Bernardino are the five most populous in the state, and are among the top 15 most populous counties in the United States.^[8]

The motion picture, television and music industry are centered in the Los Angeles area in Southern California. Hollywood, a district of Los Angeles, gives its name to the American motion picture industry, which is synonymous with the neighborhood name. Headquartered in Southern California are The Walt Disney Company (which owns ABC), Sony Pictures, Universal Pictures, MGM, Paramount Pictures, and Warner Bros. Universal, Warner Bros., and Sony also run major record companies.

Southern California is also home to a large surf and skateboard culture. Companies such as Vans, Volcom, Quiksilver, No Fear, Stüssy, RVCA, and Body Glove are all headquartered there. Skateboarder Tony Hawk; surfers Rob Machado, Timmy Curran, Bobby Martinez, Pat O'Connell, Dane Reynolds, and Chris Ward live in Southern California. Some of the most famous surf locations are in Southern California as well, including Trestles, Rincon, The Wedge, Huntington Beach, and Malibu. Some of the world's largest action sports events, including the X Games,^[9] Boost Mobile Pro,^[10] and the U.S. Open of Surfing, are held in Southern California. The region is also important to the world of yachting with premier events including the annual Transpacific Yacht Race, or Transpac, from Los Angeles to Hawaii. San Diego Yacht Club hosted the three America's Cup races from 1988 to 1995. The first modern-era triathlon was held in San Diego's Mission Bay in 1974. Since then, Southern California, and San Diego in particular, have become a mecca for triathlon and multi-sport racing, products, and culture.

Southern California has multiple sports franchises and networks, such as Fox Sports Net.

Many of these locals and tourists frequent the Southern California coast for its beaches. Some of Southern California's most popular beaches are Malibu, Laguna Beach, La Jolla, Manhattan Beach, and Hermosa Beach. Southern California is also known for its mountain resort communities, such as Big Bear Lake, Lake Arrowhead, and Wrightwood, and their ski resorts, like Bear Mountain, Snow Summit, Snow Valley Mountain Resort, and Mountain High. The inland desert city of Palm Springs is also popular.^[11]

Southern California is generally considered the area of California south of the latitude 35°45'N,^[12] approximately one-third of the state, formed by the northern boundaries of San Luis Obispo, Kern, and San Bernardino counties, which are not exactly a straight line. Another definition for Southern California uses Point Conception and the Tehachapi Mountains as the northern geographical barriers, especially when defining California's bioregions.^[13][14] In this definition, Owens Valley and Death Valley are part of the Southern California desert system.^[15] Because of the barrier formed by the Tehachapi and Sierra Nevada ranges, cartographer George Wheeler observed in 1876 that Northern California was better connected to Oregon and Nevada than it was to Southern California.^[16]

Following the acquisition of the territory of California by the United States, several pro-slavery politicians attempted to arrange the division of Alta California at 36 degrees, 30 minutes, the line of the Missouri Compromise. Instead, the passing of the Compromise of 1850 enabled California to be admitted to the Union as a free state, preventing the southern half of California from becoming its own separate slave state.

Subsequently, southern Californians dissatisfied with inequitable taxes and land laws attempted several times in the 1850s to achieve a separate statehood or territorial status separate from northern California. The only successful proposal, the Pico Act of 1859, was passed by the California State Legislature and signed by State Governor John B. Weller.^[17] It was approved overwhelmingly by nearly 75 percent of southern California voters to form the proposed Territory of Colorado. The Pico Act bisected California starting at a latitude of six standard parallels south of the Mount Diablo meridian, then ducking southward around part of the Central Valley before cutting northeast to the California border.^[18] Six standard parallels is 144 miles south of Mount Diablo—which corresponds to the current northern border of San Luis Obispo County, at the latitude 35°45'N. The proposal was sent to Washington, D.C., with a strong advocate in Senator Milton Latham. However, the secession crisis following the election of Abraham Lincoln in 1860 and the subsequent American Civil War led to the proposal never coming to a vote.^[19][20]

In 1900, the Los Angeles Times defined Southern California as including "the seven counties of Los Angeles, San Bernardino, Orange, Riverside, San Diego, Ventura, and Santa Barbara." This definition left out San Luis Obispo and Kern counties.^[21]

Southern California was the name of a proposed new state which failed to get on the 2018 California ballot. The ballot measure proposed splitting the existing state into three parts.^[22]

In December 2020, during the COVID-19 pandemic, the state government led by Governor Gavin Newsom divided the state into five regions for the purpose of issuing stay-at-home orders. The Southern California region consisted of the following counties: Imperial, Inyo, Los Angeles, Mono, Orange, Riverside, San Bernardino, San Diego, San Luis Obispo, Santa Barbara, and Ventura. However, Kern County was grouped with other counties of the San Joaquin Valley, California's central agricultural valley.^[23]

This article needs additional citations for verification. (July 2011)

Southern California consists of a heavily developed urban environment, home to some of the largest urban areas in the state, along with the Deserts of California (part of which was even proposed to become a new county due to cultural, economic and geographic differences relative to the rest of the more urban region)^[35][36][37] that have been left undeveloped. It is the third most populated megalopolis in the United States, after the Great Lakes megalopolis and the Northeast megalopolis. Much of Southern California is famous for its large, spread-out, suburban communities and use of automobiles and highways. The dominant areas are Los Angeles, Orange County, San Diego, and Riverside–San Bernardino, each of which are the centers of their respective metropolitan areas, composed of numerous smaller cities and communities. The urban area is also host to an international San Diego–Tijuana metropolitan region, created by the urban area spilling over into Baja California.

The main barrier to urbanization along the Interstate 5 corridor is Camp Pendleton. The cities and communities along Interstate 15 and Interstate 215 are so interrelated that Temecula and Murrieta have as much connection with the San Diego metropolitan area as they do with the Inland Empire. To the east, the United States Census Bureau considers the San Bernardino and Riverside County areas, Riverside-San Bernardino area as a separate metropolitan area from Los Angeles County. Newly developed exurbs formed in the Antelope Valley, north of Los Angeles, the Victor Valley, and the Coachella Valley with the Imperial Valley. Also, population growth was high in the Bakersfield-Kern County, Santa Maria, and San Luis Obispo areas.

Most of Southern California has a Mediterranean-like climate, with warm and dry summers, mild and wet winters, where cool weather and freezing temperatures are rare. Southern California contains other types of climates, including semi-arid, desert and mountain, with infrequent rain and many sunny days. Summers are hot or warm, and dry, while winters are mild, and rainfall is low to moderate depending on the area. Rain is infrequent, but is often heavy when it does occur, making flash floods an aspect of living in Southern California. This climatic pattern was alluded to in the hit song "It Never Rains (In Southern California)". While snow is very rare in lower elevations, mountains above 5,000 feet (1,500 m) receive plentiful snowfall in the winter.

Since the first decade of the 21st century, droughts and wildfires have increased in frequency as a result of climate change.^[38][39]

Southern California consists of one of the more varied collections of geologic, topographic, and natural ecosystem landscapes in a diversity outnumbering other major regions in the state and country. The region spans from Pacific Ocean islands, shorelines, beaches, and coastal plains, through the Transverse and Peninsular Ranges with their peaks, and into the large and small interior valleys, to the vast deserts of California.

Introductory categories include:

• Category: Beaches of Southern California
• Category: Mountain ranges of Southern California
• Category: Rivers of Southern California
• Category: Deserts of California
• Category: Parks in Southern California

As of the 2020 United States census, Southern California has a population of 23,762,904. Despite a reputation for high growth rates, Southern California's population has grown slower than the state average since the 2000s. This is due to California's growth becoming concentrated in the northern part of the state as result of a stronger, tech-oriented economy in the Bay Area and an emerging Greater Sacramento region.

Southern California consists of one Combined Statistical Area, eight Metropolitan Statistical Areas, one international metropolitan area, and multiple metropolitan divisions. The region is home to two extended metropolitan areas that exceed five million in population. These are the Greater Los Angeles Area at 17,786,419, and San Diego–Tijuana at 5,105,768.^[46][47] Of these metropolitan areas, the Los Angeles-Long Beach-Santa Ana metropolitan area, Riverside-San Bernardino-Ontario metropolitan area, and Oxnard-Thousand Oaks-Ventura metropolitan area form Greater Los Angeles;^[48] while the El Centro metropolitan area and San Diego-Carlsbad-San Marcos metropolitan area form the Southern Border Region.^[49][50] North of Greater Los Angeles are the Santa Barbara, San Luis Obispo, and Bakersfield metropolitan areas.

This section needs additional citations for verification. (March 2016)

Southern California is home to Los Angeles International Airport, the second-busiest airport in the United States by passenger volume (see World's busiest airports by passenger traffic) and the third-busiest by international passenger volume (see Busiest airports in the United States by international passenger traffic); San Diego International Airport, the busiest single-runway airport in the United States; Van Nuys Airport, the world's busiest general aviation airport; major commercial airports at San Bernardino, Orange County, Bakersfield, Ontario, Burbank, and Long Beach; and numerous smaller commercial and general aviation airports.

Six of the seven lines of the commuter rail system, Metrolink, run out of downtown Los Angeles, connecting Los Angeles, Ventura, San Bernardino, Riverside, Orange, and San Diego counties with the other line connecting San Bernardino, Riverside, and Orange counties directly.

Southern California is also home to the Port of Los Angeles, the country's busiest commercial port; the adjacent Port of Long Beach, the country's second busiest container port; and the Port of San Diego.

Freeways and highways

Main article: Southern California freeways

Sections of the Southern California freeway system are often referred to by names rather than by the official numbers.

More information Sign, Interstate ...

Interstate Highways

Sign	Interstate	Freeway name
	Interstate 5	Golden State Freeway Santa Ana Freeway San Diego Freeway Montgomery Freeway
	Interstate 8	Ocean Beach Freeway Mission Valley Freeway
	Interstate 10	Santa Monica (Rosa Parks) Freeway Golden State Freeway San Bernardino Freeway Indio (Dr. June McCarroll) Freeway Blythe Freeway
	Interstate 15	Mojave Freeway Barstow Freeway Ontario Freeway Corona Freeway Temecula Valley Freeway Escondido Freeway
	Interstate 40	Needles Freeway
	Interstate 105	Century (Glenn Anderson) Freeway
	Interstate 110	Harbor Freeway
	Interstate 210	Foothill Freeway
	Interstate 215	Barstow Freeway San Bernardino Freeway Moreno Valley Freeway Escondido Freeway
	Interstate 405	San Diego Freeway
	Interstate 605	San Gabriel River Freeway
	Interstate 710	Long Beach Freeway
	Interstate 805	Jacob Dekema Freeway
	Future Interstate 905

Close

More information Sign, U.S. Route ...

U.S. Highway system

Sign	U.S. Route	Freeway name
	U.S. Route 66	National Trails Highway Cajon Boulevard Foothill Boulevard Arroyo Seco Parkway Santa Monica Boulevard
	U.S. Route 95
	U.S. Route 99	Golden State Highway Ridge Route
	U.S. Route 101	Ventura Freeway Hollywood Freeway Santa Ana Freeway El Camino Real
	U.S. Route 395

Close

Public institutions in the region include:

University of California (10 campuses total; 5 within the SoCal region)

• Irvine
• Los Angeles
• Riverside
• Santa Barbara
• San Diego

California State University (23 campuses total; 12 within the SoCal region)

Private institutions include:

Numerous parks provide recreation opportunities and open space. Locations include:

Major professional sports teams in Southern California include:

• NFL (American football) Los Angeles Rams, Los Angeles Chargers
• NBA (Basketball) Los Angeles Lakers, Los Angeles Clippers
• MLB (Baseball) Los Angeles Dodgers, Los Angeles Angels, San Diego Padres
• NHL (Ice hockey) Los Angeles Kings, Anaheim Ducks
• MLS (Soccer) LA Galaxy, Los Angeles FC, San Diego FC
• NWSL(Soccer) Angel City FC, San Diego Wave FC
• WNBA(Basketball) Los Angeles Sparks

Southern California also is home to a number of popular NCAA sports programs such as the UCLA Bruins, the USC Trojans, and the San Diego State Aztecs. The Bruins and the Trojans both field football teams in NCAA Division I in the Big Ten Conference, and there is a longtime rivalry between the schools.