Riverside County

County in south California; area 18,684 sq km/7,214 sq mi; population (1990) 1,170,400. Riverside is its administrative headquarters. The county extends from the Arizona state line in the east to Orange County and the Los Angeles area in the west. The county produces citrus fruits, poultry, livestock, dairy products, grain, dates, nuts, and field and truck crops, and is increasingly industrial in the Riverside area, which is a growing high-tech business zone.

To the east, Riverside County includes several American Indian reservations and most of the Joshua Tree National Monument. In the central area are the Coachella Valley, with Palm Springs and other resorts, and part of the Salton Sea. To the west, suburbs and exurbs of the Los Angeles area have spread into the valleys between mountains of the Coast Ranges.