Trigo Mountains Wilderness is a protected desert area in southwestern Arizona, about 30 miles north of Yuma, preserving 30,300 acres and a 15-mile stretch of the rugged Trigo Mountains east of the Colorado River. Established in 1990, it helps form a broader corridor of protected lands along the Lower Colorado River Valley, adjoining nearby national wildlife refuges and surrounding desert and mountain systems. Its stark ridgelines, bajada plains, and arid mountain habitats support desert bighorn sheep, while the wider landscape also sustains mountain lions and bobcats. Historic mines along its margins reflect earlier mining in this remote region.