This map depicts the bedrock and surficial geology of most of the Cunningham Mountain 7 ½’ quadrangle in the southern Dome Rock Mountains in the lower Colorado River Valley, La Paz County, southwestern Arizona. The southern ½ of the quadrangle is on the Yuma Proving Ground, administered by the U.S. Army, which granted us access to the area. This geologic mapping is part of a multi-year AZGS effort to map the bedrock and basin geology in the lower Colorado River Valley (e.g., Gootee et al., 2016; Johnson et al., 2017; Ferguson et al., 2018). This geologic map complements 7 previous Arizona Geological Survey 7 ½’ quadrangle mapping projects in this general area, and the geologic map of the Trigo Pass 7 ½’ quadrangle immediately to the south (Ferguson and Pearthree, 2021).