“The Pentagon is the headquarters of the Department of Defense. It is one of the world's largest office buildings. It is twice the size of the Merchandise Mart in Chicago, and has three times the floor space of the Empire State Building in New York. The Pentagon is virtually a city in itself.”
A guided tour of The Pentagon is an interesting thing to do for visitors, and something I would want to do next time I will be there.
These quick snapshots of The Pentagon were taken while crossing the street from the Metro station, in May 2008 during a memorable trip in Washington DC.