Alta Loma is one of three formerly unincorporated areas that became part of the city of Rancho Cucamonga, California state in 1977. The community is located in the foothills of the south face of the San Gabriel Mountain range, near Cucamonga Peak and Mount Baldy. At its highest point the elevation is about 3000 feet. The name Alta Loma comes from the Spanish, meaning "high hill" or "high hillside.
It is almost completely residential and as per city ordinance no commercial business may exist above 19th Street. The only exception is given to several businesses that were already in place when the ordinance was enacted.