With more than 1,200 square miles of land area, U.S. Army Yuma Proving Ground (YPG) is the fourth-largest installation in the ...

The wall is being built through the Cabeza Prieta National Wildlife Refuge, home to the endangered Sonoran pronghorn, and the rugged Tinajas Altas Mountains in the Barry M. Goldwater Bombing Range ...

Arizona is a state with many high mountain ranges and tall dormant volcanoes ... is just 70 feet above sea level and is located in Yuma County along the Colorado River just west of San Luis ...