The Cabeza Prieta National Wildlife Refuge was established in the late 1930s and today exists as the third-largest refuge in the contiguous United States. More than 275 species of animal call Cabeza Prieta home, although we saw little more than footprints. This area has been in recent news headlines for crackdowns on humanitarian aid and arrests of workers providing water to immigrants entering the US. Travel and camping within the refuge is permitted following registration. Facilities are very limited so bring water, food and all weather clothing.