History of the United States (1991–2008) South Tower less than twenty minutes later at 9:03 A.M. (EST), resulting in the collapse of both 110 story skyscrapers, and the destruction of the World Trade Center. The third hijacked plane, American Airlines Flight 77, was crashed into the Pentagon (the headquarters of the United States Department of Defense) in Arlington County, Virginia, demolishing a section of the outer southwest facing wall. After discovering that their plane, United Airlines Flight 93, was going to be used as a missile, passengers attempted to regain control of the plane which had been redirected towards Washington, D.C. However, after regaining control from
United States Post Office (Arlington, Virginia) United States Post Office (Arlington, Virginia) US Post Office-Arlington is a historic post office building located in the Clarendon neighborhood of Arlington, Virginia. It was designed and built in 1937, and is one of a number of post offices designed by the Office of the Supervising Architect of the Treasury Department under Louis A. Simon. The building is a one-story, pentagonal shaped brick building in the Georgian Revival style. Atop the entrance portico is a dome that rises above the buildings flat roof and is supported by four fluted limestone piers. The interior features murals by Auriel Bessemer picturing Indians