Known as the "Home of Ordnance," Aberdeen Training Ground is one of the Army's finest test, evaluation, research, development, engineering, and training installations in the world. ATG was established on October 20, 1917, six months after the United States entered World War I. The post officially opened on December 14, 1917 with the first gun being fired on January 2, 1918. Aberdeen was used for proof-testing field artillery weapons, ammunition, trench mortars, air defense guns, and railway artillery. The mission of the proving ground was later expanded to include the operation of an Ordnance training school and the developmental testing of small arms. The Army's ordnance training was consolidated at the proving ground during the Second World War. Today, the U.S. Army Ordnance Center and School provides mechanical maintenance training for more than 20,000 U.S. and foreign personnel every year.
Aberdeen Proving Ground occupies more than 72,500 acres in Harford County, Md. Its northernmost point is marked by the meeting of the Susquehanna River and the Chesapeake Bay. On the south it is bordered by the Gunpowder River. The nearby locality offers picturesque beauty, bustling urban centers, historic harbor towns, and a variety of world-class cultural and sports amenities.