California State Route 371 connects SR 79 at Aguanga with SR 74 in the San Bernardino National Forest via the Cahuilla Indian Reservation, Lake Riverside and Anza. It is part of an east-west corridor formed by parts of SR 79, SR 371, and SR 74 between Temecula and the Palm Springs-Coachella Valley area. The same east-west corridor serves as a popular short cut for motorists traveling between San Diego County and Palm Springs-Coachella Valley regions for the spectacular scenery and shorter distance (by 25 miles) versus the heavily congested freeway route via Interstates 10, 15 and 215.
SR 371 is a remnant of a much longer SR 71, back when that route used to extend southeast from Corona via the current Interstate 15 to Lake Elsinore and Temecula, and then turned east along SR 79. When SR 71 was decommissioned in favor of I-15 between Temecula and Corona (in 1973-1974), the shared alignment became solely known as SR 79, and the remnant alignment was given the new SR 371 designation.