The Peloncillo region and its ranges, connecting valleys, and drainages encompass a landscape that includes an international border and the boundaries between four states: Arizona and New Mexico in the United States, and Sonora and Chihuahua in Mexico.
The Peloncillo Mountains and its surrounding valleys, ranges and drainages anchor the center of the Sky Island region—a region of the southwestern United States and northwestern Mexico characterized by isolated mountain ranges separated by desert and grassland. The Peloncillo region is in a unique geographic position that has shaped its rich natural and cultural heritage. It straddles the Arizona and New Mexico boundary in the United States, crosses the international boundary and straddles the Sonora and Chihuahua border in Mexico.
