Lt. Col. Hugh Tracey and architect George Bergstrom conceived this building's five-corner design during a feverish summer weekend early in World War II.
If you have a meeting at the Pentagon and need to park, do so at the Pentagon City Mall and metro one stop. Closer than the visitor's spots in North Parking (and a warmer walk!)
Beware of lines, visitors. Processing through security can take up to an hour. Lines are sometimes outdoors, so of you're unable to be in the heat for health reasons plan accordingly :)
The tour was quick, and I left feeling that I wasn't sure if it was really worth doing. I don't think it would be a top thing I would recommend visitors do in DC. I did enjoy the 9/11 Memorial though.