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The Pentagon

The headquarters of the United States Department of Defense lies on the west bank of the Potomac River in Arlington, Virginia, directly across from Washington, D.C.

Built in the form of a pentagon (hence the name), the building's five concentric rings are connected by 10 spokelike corridors. It has five floors, a mezzanine, and a basement. The building covers 29 acres and has 3,705,793 square feet of office and other space, making it the largest office building in the United States. In fact, it is so large that it even has its own Zip Code and post office. The building's layout is so efficient, however, that it takes only seven minutes for the average person to walk between any two points in the building.

The Pentagon


The concept of bringing all the various offices within the War Department into a single building was first proposed by Brigadier General Brehon B. Sommervell, Chief of the Construction Division of the Office of the Quartermaster General, in mid-July 1941. The groundbreaking ceremony took place on September 11, 1941, just three months before the United States was drawn into World War II. Construction pushed on during the war, and the building was dedicated on January 15, 1943, nearly sixteen months to the day after the groundbreaking. The building cost $83,000,000 to construct.

Facts and Figures

Employees ~23,000, both military and civilian, plus ~3,000 non-defense support personnel
Corridors 17.5 miles
Surrounding Grounds 200 acres
Parking Lots
Parking Spaces ~8,770
Stairways 131
Escalators 19
Clocks 4,200
Water Fountains 691
Restrooms 284
Telephone Cable
100,000 miles

See Also

World War II

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The Robinson Library >> Armies

This page was last updated on 01/15/2019.