About this Unit
**USAD The Pentagon** is not a traditional military unit but serves as the headquarters of the United States Department of Defense. Completed in 1943, The Pentagon is located in Arlington, Virginia, and is one of the world’s largest office buildings. It houses the offices of the Army, Navy, Air Force, and Marine Corps leadership, facilitating command and control of U.S. military operations worldwide. Throughout its history, The Pentagon has coordinated U.S. military efforts during major conflicts, including World War II, the Korean War, the Vietnam War, and the Global War on Terrorism.
Historical Facts
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Origin During WWII: The Pentagon was conceived in 1941 to consolidate the rapidly expanding War Department during World War II, as staff were scattered across 17 buildings in Washington, D.C.
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Record Construction Speed: The building was constructed in just 16 months, starting in September 1941 and officially dedicated on January 15, 1943.
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World’s Largest Office Building: Covering 6.5 million square feet, the Pentagon is the world’s largest office building by floor area, with about 17.5 miles of corridors.
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Initial Design to Avoid Swamp: The original site was a swampy area, and the unique five-sided shape was chosen to fit the available land, although the final location changed, the design remained.
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Symbol of U.S. Military: "The Pentagon" is commonly used as a metonym for the entire U.S. Department of Defense and the U.S. military leadership.
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Attack on September 11, 2001: The Pentagon was hit by American Airlines Flight 77 during the 9/11 terrorist attacks, killing 125 people in the building and 59 on the plane.
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Pentagon Papers: The term "Pentagon Papers" refers to the secret Department of Defense study of U.S. political and military involvement in Vietnam, leaked in 1971, causing a major political scandal.
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Secret Underground Bunkers: The Pentagon has extensive underground tunnels, a bunker complex, and secure communications facilities, some of which remain classified.
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Eco-Friendly Features: The Pentagon was originally built with ramps instead of elevators due to a steel shortage in WWII, making it more accessible and energy-efficient.
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Largest Memorial Chapel: After 9/11, the Pentagon Memorial Chapel was built inside the building, serving as a place of reflection for all faiths and the largest such chapel in a U.S. federal building.
