Spread out along 20 miles of Chesapeake Bay, Aberdeen Proving Ground is home to a diverse array of weapons development and testing programs. The installation covers 72,516 acres, ranging from heavily industrialized areas (the base has over 2,000 buildings) to remote testing ranges on peninsulas, bays, and tidal areas. The Edgewood area of the Proving Ground has been the nation's primary chemical and biological weapons development location since World War I, and is now littered with contamination and unexploded chemical weapons. Over 15,000 employees work at Aberdeen Proving Ground.