1931 Map of Vallecito

About this map

The Santa Rosa Mountains and the Vallecito Mountains dominate this 1931 topographic study of the arid interior where San Diego and Riverside counties meet. This document represents a synthesis of earlier fieldwork, combining a 1901 survey of the north with a 1913 reconnaissance of the south to illustrate the stark landscape of the Salton Basin. In this era before widespread development, water sources define the human geography, marked by isolated points like Borego Springs, the Hanna Drill Hole Water, and the intermittent Clark Lake. The presence of several I.R. (Indian Reservation) tracts and the home of Fig Tree John near the shoreline of the Salton Sea provide critical data for researchers of early 20th-century desert habitation. The map also traces the Riverside San Diego Boundary Line as it cuts through the complex terrain of the San Felipe Mts.