California is a state on the West Coast of the United States, along the Pacific Ocean. It is bordered by Oregon to the north, Nevada to the east, Arizona to the southeast, and to the south the Mexican state of Baja California. California is the most populous U.S. state. Its four largest cities are Los Angeles, San Diego, San Jose, and San Francisco. It is known for its varied climate and geography as well as its diverse population. The area known as Alta California was colonized by the Spanish Empire beginning in the late 18th century. It and the rest of Mexico became an independent republic in 1821. In 1846 California broke away from Mexico, and after the Mexican-American War, Mexico ceded California to the United States. California became the 31st state admitted to the United States on September 9, 1850.
California is the third-largest U.S. state by land area after Alaska and Texas, and preceding Montana. Its geography ranges from the Pacific coast to the Sierra Nevada mountain range in the east, to Mojave desert areas in the southeast and the Redwood-Douglas fir forests of the northwest. The center of the state is dominated by the Central Valley, one of the most productive agricultural areas in the world. California adjoins the Pacific Ocean, Oregon, Nevada, Arizona, and the Mexican state of Baja California. With an area of 160,000 square miles (414,000 km), it is the third largest state in the United States in size, after Alaska and Texas. If it were a country, California would be the 59th largest in the world in area.
The California Gold Rush dramatically changed California with a large influx of people and an economic boom which caused San Francisco to grow from a tiny hamlet of tents to a world renowned boomtown in the 19th century. The early 20th century was marked by Los Angeles becoming the center of the American entertainment industry, in addition to the growth of a large tourism sector in the state. Along with Central California's prosperous agricultural industry, other industries include aerospace, petroleum, and computer and information technology. California ranks amongst the ten largest economies in the world, and were it a separate country, it would be 35th among the most populous countries, with a GDP similar to France.
Bridalveil Fall flows from a U-shaped hanging valley that was created by a tributary glacier. Mt. Shasta overlooks the town of the same name. The Sierra Nevada (Spanish for "snowy range") include the highest peak in the contiguous forty-eight states, Mount Whitney, at 14,505 ft (4,421 m). The range embraces Yosemite Valley, famous for its glacially carved domes, and Sequoia National Park, home to the giant sequoia trees, the largest living organisms on Earth, and the deep freshwater lake, Lake Tahoe, the largest lake in the state by volume. California is famous for earthquakes due to a number of faults, in particular the San Andreas Fault. It is vulnerable to tsunamis, floods, droughts, Santa Ana winds, wildfires, and landslides on steep terrain, and has several inactive volcanoes
To the east of the Sierra Nevada are Owens Valley and Mono Lake, an essential migratory bird habitat. In the western part of the state is Clear Lake, the largest freshwater lake by area entirely in California. Though Lake Tahoe is larger, it is divided by the California/Nevada border. The Sierra Nevada falls to Arctic temperatures in winter and has several dozen small glaciers, including Palisade Glacier, the southernmost glacier in the United States.
About 45 percent of the state's total surface area is covered by forests, and California's diversity of pine species is unmatched by any other state. California contains more forestland than any other state except Alaska. Many of the trees in the California White Mountains are the oldest in the world; one Bristlecone pine has an age of 4,700 years.
In the south is a large inland salt lake, the Salton Sea. Deserts in California make up about 25 percent of the total surface area. The south-central desert is called the Mojave; to the northeast of the Mojave lies Death Valley, which contains the lowest, hottest point in North America, Badwater Flat. The distance from the lowest point of Death Valley to the peak of Mount Whitney is less than 200 miles (322 km). Indeed, almost all of southeastern California is arid, hot desert, with routine extreme high temperatures during the summer.
Along the California coast are several major metropolitan areas, including Greater Los Angeles, the San Francisco Bay Area, and San Diego.
California is famous for earthquakes due to a number of faults, in particular the San Andreas Fault. It is vulnerable to tsunamis, floods, droughts, Santa Ana winds, wildfires, and landslides on steep terrain, and has several inactive volcanoes.
California climate varies from Mediterranean to subarctic. Much of the state has a Mediterranean climate, with cool, rainy winters and dry summers. The cool California Current offshore often creates summer fog near the coast. Further inland, one encounters colder winters and hotter summers.
Northern parts of the state average higher annual rainfall than the south. California's mountain ranges influence the climate as well: some of the rainiest parts of the state are west-facing mountain slopes. Northwestern California has a temperate climate, and the Central Valley has a Mediterranean climate but with greater temperature extremes than the coast. The high mountains, including the Sierra Nevada, have a mountain climate with snow in winter and mild to moderate heat in summer.
The east side of California's mountains has a drier rain shadow. The low deserts east of the southern California mountains experience hot summers and nearly frostless mild winters; the higher elevation deserts of eastern California see hot summers and cold winters. In Death Valley, the highest temperature in the Western Hemisphere, 134 °F (57 °C), was recorded July 10, 1913.