Yuma Proving Ground (YPG) is a United States Army facility and one of the largest military installations in the world. Situated in southwestern La Paz County and western Yuma County in southwestern Arizona, U.S., approximately 30 miles (48 km) north-east of the city of Yuma, the proving ground is used for testing military equipment and encompasses 1,307.8 square miles (3,387.2 km²) in the northwestern Sonoran Desert.
The proving ground conducts tests on nearly every weapon system in the ground combat arsenal. Munitions and artillery systems are tested here in an area almost completely removed from urban encroachment and noise concerns. Restricted airspace controlled by the test center amounts to over 2,000 square miles (5,000 km2). Over 3000 people, mostly civilian, work at the proving ground. It is a major economic player in Yuma County, with an economic impact of over $430 million annually. Yuma Proving Ground is the largest single employer of civilians in the county.
In a typical year, over 500,000 artillery, mortar and missile rounds are fired, 36,000 parachute drops take place, 200,000 miles (320,000 km) are driven on military vehicles, and over 4000 air sorties are flown from the proving ground’s Laguna Army Airfield. Though about 90 percent of the proving ground's workload is devoted to the test and evaluation of weapon systems and munitions, training activities are important. Dozens of units visit the proving ground each year for realistic desert training, especially before deploying overseas.
Yuma Proving Ground features the longest overland artillery range (40 miles or 64 kilometres) in the nation, the most highly instrumented helicopter armament test range in the Department of Defense, over 200 miles (300 km) of improved road courses for testing tracked and wheeled military vehicles, over 600 miles (1,000 km) of fiber-optic cable linking test locations, and the most modern mine and demolitions test facility in the western hemisphere. Realistic villages and road networks representing urban areas in Southwest Asia have been constructed and are used for testing counter-measures to the threat of roadside bombs.