The Imperial Valley lies in the California counties of Imperial and Riverside in southeastern Southern California with an urban area centered on the city of El Centro. The Valley is bordered by the Colorado River to the east and, in part, the Salton Sea to the west. Farther west lies the San Diego and Imperial County border. To the north is the Coachella Valley region of Riverside County, which together with Imperial Valley form the Salton Trough, or the Cahuilla Basin, also the county line of Imperial and Riverside counties, and to the south the international boundary with the U.S. state of California and Baja California.
The culture of the area blends those of the United States and Mexico, due to its regional history and geographic location along the international border. The Imperial Valley economy is based on agriculture.
Imperial Valley was so named by the Imperial Land Company, in hopes of attracting settlers. It is now the home of the El Centro metropolitan area and also an economic center of California's government defined "South Border". Locally, the terms "Imperial Valley" and "Imperial County" are used synonymously.