California is the most populous state in the United States and the third-largest by land area, after Alaska and Texas. California is also the most populous sub-national entity in North America. It is located on the U.S. West Coast, bordered by the Pacific Ocean to the west and by the states of Oregon to the north, Nevada to the east, Arizona to the southeast, Baja California, Mexico, to the south.

Its 5 largest cities are Los Angeles, San Diego, San Jose, San Francisco, and Long Beach, with Los Angeles, San Diego, and San Jose each having at least 1 million residents. Like many populous states, California's capital, Sacramento is smaller than the state's largest city, Los Angeles.

California has a varied climate and geography and a multi-cultural population. California's geography ranges from the Pacific Coast to the Sierra Nevada Mountains in the east, to the 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.