1964 Map of Mule Wash

About this map

The Colorado River serves as the dividing line between California and Arizona in this mid-1960s survey, marking the transition from the agricultural Palo Verde Valley to the arid reaches of the Yuma Proving Ground. West of the river, an intricate network of irrigation infrastructure including the D-23 Canal and various spills and drains supports the valley’s fertile land. To the east, the landscape shifts abruptly toward the Trigo Mountains, where the terrain is defined by a series of desert drainages like Mohave Wash and Mule Wash. A primitive network of jeep trails and the unpaved Cibola Road provide the only transit through the military proving grounds, illustrating the isolation of this borderland region before modern development. Notable landmarks for researchers include a Borrow Pit near the river and numerous named washes such as Gould Wash and Crazy Woman Wash.