The Pentagon The Pentagon The Pentagon, in Arlington County, Virginia, across the Potomac River from Washington, D.C., is the headquarters of the United States Department of Defense. As a symbol of the U.S. military, the phrase "The Pentagon" is often used as a metonym for the Department of Defense and its leadership. The building was designed by American architect George Bergstrom and built by contractor John McShain. Ground was broken on September 11, 1941, and the building was dedicated on January 15, 1943. General Brehon Somervell provided the major motivating power behind the project; Colonel Leslie Groves was responsible for overseeing the
Construction of the Virginia approaches to Arlington Memorial Bridge early 1931, Arlington Memorial Bridge was nearing completion, but citizens of Arlington County had no way of using the bridge as no approaches had been approved by the state or county in the preceding five years. Arlington County itself took no action on any bridge approaches until January 1931, when it began tentatively surveying potential routes. In February 1931, citizens of Clarendon, Ft. Myer Heights, and Lyon Village — unincorporated communities north and northwest of Arlington National Cemetery — met with the Arlington County Board of Supervisors and a Commonwealth's Attorney from the state of Virginia to identify a route