1918 Map of Mt. Riley

About this map

The United States Mexico international boundary defines the southern limit of this 1917 military-focused survey, where the prominent volcanic peak of Mt Riley rises above the Chihuahuan Desert. The landscape is dominated by the sprawling volcanic fields of the West Potrillo Mountains and the distinct ridgeline of the East Potrillo Mts. Transportation through this arid corridor relied heavily on the El Paso and Southwestern railroad, which arcs across the southern portion of the sheet near a marker labeled Monument. Remote ranching operations, such as Phillips Ranch and Cox Ranch, represent the sparse human footprint in this borderland, supported by essential water infrastructure like Cox Tank. The survey reflects a strategic wartime effort by the War Department to document the difficult terrain of Doña Ana County during a period of heightened border security.