1939 Map of Trigo Peaks

About this map

The Gila and Salt River Base Line cuts across this arid landscape in Yuma County, establishing a primary survey reference point amid a complex system of mountains and washes. The topography is dominated by the North Trigo Peaks and South Trigo Peaks, which rise sharply above the La Posa Plain. Water management in this desert environment is recorded through scattered landmarks such as White Tanks and Mohave Tanks, essential stopping points for travelers moving through the high passes. Historically, the area facilitated transit via the Cibola Road, which winds through the Trigo Mountains. Resource extraction is evidenced by the Tweed Mine located in the southern reaches of the quadrangle. The map details a network of dry drainages, including Trigo Wash and Mohave Wash, which define the erosion patterns of the Dome Rock Mountains and the northern Chocolate Mountains.