The Pentagon

The Pentagon is the headquarters of the United States Department of Defense located in Arlington County, Virginia, just across the Potomac River from Washington, D.C. It is a five-sided, five-storey building completed during World War II and is one of the largest office buildings in the world by floor area.

The building’s distinctive plan consists of five concentric rings connected by radial corridors surrounding a central plaza, providing organized office space and internal circulation for thousands of employees. The adjacent Pentagon Memorial commemorates those who died in the 2001 attack on the building and is open to the public.

Designed and built rapidly between 1941 and 1943 to consolidate defense offices, the Pentagon has since served as the administrative centre of the U.S. military establishment and undergone periodic renovations and security upgrades. It sustained damage in the 2001 terrorist attack and was repaired and restored in the following years.

The Pentagon sits in Arlington County, Virginia, on the Potomac’s western bank about 5 kilometres southwest of the U.S. Capitol and is connected to Washington by the Theodore Roosevelt Bridge and nearby Metro and road links.

• Size and date: Construction took place during World War II, with the building completed in 1943; it is the world's largest office building by floor area at about 6.5 million square feet.
• Visitor access: Public tours are available but must be booked in advance and require security screening; visitors should check current access rules before planning a visit.

What to See #

• Pentagon Memorial: The Pentagon Memorial - an outdoor commemorative site adjacent to the building honoring the 184 people killed at the Pentagon on September 11, 2001.
• Five-ring structure: Five concentric rings and radial corridors - the building's internal ring-and-spoke layout surrounds a central open courtyard and organizes office space across five rings.