2015 Map of Shell Reef

About this map

The boundary between San Diego County and Imperial County cuts vertically through this arid landscape, where the shifting sands of the Imperial Valley meet the rising elevations of the desert floor. Water is the primary architect here, evidenced by the intricate branching of Tule Wash, Arroyo Salada, and the larger San Felipe Creek system to the south. Historically significant water sources like Five Palms Spring and Barrel Spring provide critical landmarks in a region otherwise defined by dry washes and geological formations like the fossil-rich Shell Reef. The presence of the Cahuilla Trail suggests long-standing transit corridors through the basin. In the southwest, Squaw Peak stands as a prominent topographical marker above the seasonal waters of Benson Lake, reflecting the extreme variations in desert hydrology.