San Bernardino County, officially the County of San Bernardino, is a county located in the southern portion of the U.S. state of California. As of the 2010 census, the population was 2,035,210, making it the fifth-most populous county in California, and the 12th-most populous in the United States. The county seat is San Bernardino.
San Bernardino County is included in the Riverside-San Bernardino-Ontario, CA Metropolitan Statistical Area, also known as the Inland Empire, as well as the Los Angeles–Long Beach, CA Combined Statistical Area.
With an area of 20,105 square miles, San Bernardino County is the largest county in the United States by area, although some of Alaska’s boroughs and census areas are larger. It is larger than each of the nine smallest states, larger than the four smallest states combined, and larger than 70 different sovereign nations.
Located in southeast California, the thinly populated deserts and mountains of this vast county stretch from where the bulk of the county population resides in two Census County Divisions, some 1,422,745 people as of the 2010 Census, covering the 450 square miles (1,166 km2) south of the San Bernardino Mountains in San Bernardino Valley, to the Nevada border and the Colorado River.