State Route 86 is a north–south state highway in the U.S. State of California that connects the Imperial and Coachella valleys in the southeastern desert region of the state. It runs from State Route 111 near the Mexican border crossing at Calexico north through the Imperial Valley via El Centro and Brawley, and around the west side of the Salton Sea into the Coachella Valley. It then goes through Coachella before terminating at Interstate 10 in Indio.

The Imperial Valley of Southern California lies in Imperial and Riverside counties, 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 Mexico.