Aberdeen Proving Ground, the Army's oldest active proving ground, was established on October 20, 1917, six months after the United States entered World War I, to provide the military a facility where design and testing of ordnance materiel could be carried out in close proximity to the nation's industrial and shipping centers. The post officially opened on December 14, 1917, and the first gun was fired on January 2, 1918.

Aberdeen Proving Ground occupies more than 72,500 acres in Harford County, Md. Its northernmost point is marked by the confluence of the Susquehanna River and the Chesapeake Bay. On the south it is bordered by the Gunpowder River.

The installation comprises two principal areas, separated by the Bush River. The northern area is known as the Aberdeen Area, and the southern sector, formerly Edgewood Arsenal (established in November,1917 - as a chemical weapons research, development and testing facility), is the Edgewood Area. The two areas were administratively combined in 1971. APG property not attached to the main installationincludes the Churchville Test Site in Harford County and Carroll Island and Graces Quarters in Baltimore County.

Aberdeen Proving Ground is home to more than 50 tenants and a host of satellite activities. Among the major tenants are the U.S. Army Soldier, Biological and Chemical Command (APG's parent command), U.S. Army Ordnance Center and School, U.S. Army Developmental Test Command , U.S. Army Aberdeen Test Center , U.S. Army Center for Health Promotion and Preventive Medicine , Northeast Region Civilian Personnel Operations Center, U.S. Army Medical Research Institute of Chemical Defense , Program Manager for Chemical Demilitarization, 203rd Technical Intelligence Unit, and major elements of the Army Research Laboratory.

As a center for Army materiel testing, laboratory research and military training, the post is a key element in the nation's defense. All tanks and wheeled vehicles which have served U.S. forces for the past 50 years have been tested for performance and durability at APG - from the M4 Sherman tank of World War II to the M1 tank and High Mobility Multipurpose Wheeled Vehicle of today.

Known as the "Home of Ordnance," APG has been training Army ordnance personnel since 1918. The Army's ordnance training was consolidated at the proving ground during World War II, and today the U.S. Army Ordnance Center and School provides mechanical maintenance training for more than 20,000U.S. and foreign personnel each year. also is regimental headquarters for the Army's Chief of Ordnance.

APG's Edgewood Area has been a center for chemical warfare research and development since it was established. From the trenches of France and Belgium in World War I to the desert battlefields of Iraq nearly 75 years later, the work done at APG has contributed to the defense and safety of American forces threatened by chemical weapons.

More than 7,500 civilians work at Aberdeen Proving Ground, and more than 3,900 military personnel are assigned there. In addition, there are nearly 3,000 contractor and private business employees working on the proving ground.
There are 2,700 military family members living on the post and another 243 off post. The post supports more than 16,000 military retirees and retiree family members. The post is Harford County's largest employer and one of the largest employers in the state of Maryland.

During FY 1999, APG's total expenditures were nearly $2.3 billion. Expenditures included an installation payroll of $545.4 million, of which $520.0 million was paid to employees who live in Harford County; $666.3 million on contracts, with $80.6 million awarded to companies in Harford County; and $171.7 million on other installation costs. The total economic impact on the county (payroll and contracts) was $520.9 million.

U.S. Army Garrison, Aberdeen Proving Ground, provides general, administrative and logistical support to the post's tenants and satellite activities, and is responsible for the management and operation of the entire installation, which in many ways is like a small city.

APG has more than 2,200 buildings with more than 15 million square feet of building space. The post has more than 300 miles of improved roads, 30 miles of railroad and more than 567,000 square yards of airfield pavement. Its electrical distribution systems totals nearly 2.25 million linear feet. It has more than 215,000 linear feet of steam and hot water distribution lines. The post has nearly 21,000mn linear feet of gas distribution lines. APG's water distribution system can handle as much as 7 million gallons a day and its sewer facilities have a daily capacity of 4 million gallons. The post operates a fleet of more than 1,000 vehicles of all types and sizes.

Environmental stewardship is an essential component of all activity at APG. The installation and its tenants are actively involved in a wide variety of environmental compliance, pollution prevention, conservation, and restoration programs. In FY 1999, APG spent a total of $47.8 million on environmental programs, installation programs and installation restoration activities.