The Pentagon

The Pentagon is the headquarters of the United States Department of Defense and is located in Arlington, Virginia. As a symbol of the US military, the phrase "the Pentagon" is often used to refer to the Department of Defense rather than the building itself.

The Pentagon is one of the world's largest office buildings. It houses approximately 23,000 military and civilian employees and about 3,000 non-defense support personnel. It has five sides, five floors above ground, two basement levels, and five ring corridors per floor for a total of 17.5 miles of corridors.

The central plaza, informally referred to as "ground zero," based on the presumption that it would be a target for a Soviet nuclear missile, totals five acres and contains a snack bar called the "Ground Zero Cafe."

The building was dedicated on January 15, 1943 after ground was broken for construction on September 11, 1941. It was designed by Architect George Edwin Bergstrom and built by Philadelphia, Pennsylvania general contractor John McShain. Colonel Leslie Groves, who later administrated the Manhattan Project, oversaw its construction from 1940 to 1942.

On the evening on March 4, 2010, 3 people were shot at the Pentagon Metro, causing a lockdown of The Pentagon. Two of the victims were Pentagon police officers, and the other is the alleged suspect. One of the victims was treated on the scene for minor injuries, while the other two were taken to George Washington Hospital. The two officers were treated for minor injuries, while the suspect is in critical condition.http://www.myfoxdc.com/dpp/news/local/3-shot-outside-pentagon-metro-station-030410 http://www.msnbc.msn.com/id/35716821/ns/us_news-crime_and_courts/

• Official Site: Pentagon Tours