The Santa Rosa Mountains extend for approximately 30 miles (48 km) along the western side of the Coachella Valley within Riverside, San Diego, and Imperial Counties in Southern California.

[2] The oldest accounts of the southeastern reaches of the Santa Rosa Mountains survive from the 1774 Spanish expedition led by explorer Juan Bautista de Anza into colonial Las Californias through the Coachella Valley from the populated Viceroyalty of New Spain region (present day Mexico).

[3] 19th century maps of the region show the Santa Rosas as a southern extension of the higher northern San Jacinto Mountains.

[4] Also in the eastern Santa Rosa Mountains, in canyons with natural oases, the native California fan palm (Washingtonia filifera) is found.

[6][7] The southern portion of the range, with Toro Peak, is west of the Salton Sea and within the northeastern Borrego Badlands area of the expansive Anza-Borrego Desert State Park.