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
Arlington House, The Robert E. Lee Memorial of Alexandria County to Arlington County to end ongoing confusion between Alexandria County and the independent city of Alexandria. The name Arlington was chosen to reflect the presence of the Arlington estate. On March 4, 1925, the 68th United States Congress enacted Public Resolution 74, which authorized the restoration of the Lee Mansion in the Arlington National Cemetery, Virginia. The War Department then began to restore Arlington House, and the Department of the Army continues to manage over half of the original plantation's 1,100 acres, as Arlington National Cemetery. However, for several years after Congress enacted the authorizing legislation, the