The Pentagon Memorial, formally the National 9/11 Pentagon Memorial, located just southwest of the Pentagon in Arlington County, Virginia, across the Potomac River from Washington, D.C., is a permanent outdoor memorial to the 184 people who died as victims in the building and on American Airlines Flight 77 during the September 11 attacks.
A photo of the monument, shortly before it opened
Preparing to lower the flag at the Pentagon on October 11, 2001
America's Heroes Memorial opened in September 2002
Keith Kaseman and Julie Beckman present the design at a Pentagon press conference March 3, 2003
The Pentagon is the headquarters building of the United States Department of Defense, in Arlington County, Virginia, across the Potomac River from Washington, D.C. The building was constructed on an accelerated schedule during World War II. 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.
A view of The Pentagon from the south in September 2007
The main Navy Building (foreground) and the Munitions Building were temporary structures built during World War I on the National Mall. The Department of War was headquartered in the Munitions Building for several years before moving into the Pentagon.
The Hall of Heroes on the Pentagon's main concourse
Military police keep back Vietnam War protesters during their sit-in at the Pentagon's National Mall entrance on 21 October 1967
