Aberdeen Proving Ground Aberdeen Proving Ground (APG) is a 113 square mile U.S. Army facility located adjacent to Aberdeen. More than 7,500 civilians and 5,000 military personnel work at APG. There are 11 major commands among the tenant units. APG is the U.S. Army's oldest active proving ground, established on 20 October 1917, six months after the U.S. entered World War I. The planning and construction were overseen by Brigadier General Colden Ruggles, who later served as the Army's Chief of Ordnance. Its location allowed design and testing of ordnance materiel to take place near contemporary industrial and shipping centers. The proving ground was created as a successor to the Sandy Hook Proving Ground, which was too small for some of the larger weapons being tested. At the peak of World War II, APG had billeting space for 2,348 officers and 24,189 enlisted personnel. (Wikipedia)