The Pentagon

The Pentagon, headquarters of the Department of Defense, is one of the world's largest office buildings. It is twice the size of the Merchandise Mart in Chicago, and has three times the floor space of the Empire State Building in New York. The National Capitol could fit into any one of the five wedge-shaped sections.

The Pentagon—a building, institution, and symbol—was conceived at the request of Brigadier General Brehon B. Sommervell, Chief of the Construction Division of the Office of the Quartermaster General, on a weekend in mid-July 1941. The purpose was to provide a temporary solution to the War Department's critical shortage of space. The groundbreaking ceremony took place on September 11, 1941. The building was dedicated on January 15, 1943, nearly 16 months to the day after the groundbreaking.

The original site chosen for the Pentagon was a tract of land known as Arlington Farms. The site was bordered by five roadways thus dictating the concept of a pentagonal shaped building. Fearing the enormous building would interfere with the view of Washington, D.C. from Arlington Cemetery, President Franklin Delano Roosevelt directed the building be moved three quarters of a mile down river. The new location chosen was at the site of the old Hoover Airport, a brick factory, a pickle factory, a race track, and a low-income residential area known as Hell’s Bottom. On this site, the final design concept of an open air court surrounded by five concentric pentagonal rings (or corridors) traversed by ten spoke-like corridors was constructed.

The architectural style of the Pentagon is Stripped Neo-Classical. The building was constructed out of reinforced concrete made from 380,000 tons of sand dredged from the Potomac River and supported by 41,492 concrete piles. The designers’ ingenuity not only created a building that reflected the architectural style of the nation’s Capitol but also saved enough steel to build one battleship. At the height of construction, over 1,000 architects worked in an adjacent hanger producing enough prints to supply the 14,000 construction workers and tradesmen. Three shifts worked 24 hours a day, every day, constructing the Pentagon wedge by wedge. These wedges were occupied as they came on-line. The building was dedicated on January 15, 1943, nearly 16 months to the day after the groundbreaking.

The Pentagon is virtually a city in itself. Approximately 23,000 employees, both military and civilian, contribute to the planning and execution of the defense of our country. These people arrive daily from Washington, D.C. and its suburbs over approximately 30 miles of access highways, including express bus lanes and one of the newest subway systems in our country. They ride past 200 acres of lawn to park approximately 8,770 cars in 16 parking lots; climb 131 stairways or ride 19 escalators to reach offices that occupy 3,705,793 square feet. While in the building, they tell time by 4,200 clocks, drink from 691 water fountains, utilize 284 rest rooms, consume 4,500 cups of coffee, 1,700 pints of milk and 6,800 soft drinks prepared or served by a restaurant staff of 230 persons and dispensed in 1 dining room, 2 cafeterias, 6 snack bars, and an outdoor snack bar. The restaurant service is a privately run civilian operation under contract to the Pentagon.

Over 200,000 telephone calls are made daily through phones connected by 100,000 miles of telephone cable. The Defense Post Office handles about 1,200,000 pieces of mail monthly. Various libraries support our personnel in research and completion of their work. The Army Library alone provides 300,000 publications and 1,700 periodicals in various languages.

Stripped of its occupants, furniture and various decorations, the building alone is an extraordinary structure. Built during the early years of World War II, it is still thought of as one of the most efficient office buildings in the world. Despite 17.5 miles of corridors it takes only seven minutes to walk between any two points in the building.

The original site was nothing more than wasteland, swamps and dumps. 5.5 million cubic yards of earth, and 41,492 concrete piles contributed to the foundation of the building. Additionally, 680,000 tons of sand and gravel, dredged from the nearby Potomac River, were processed into 435,000 cubic yards of concrete and molded into the Pentagon form. The building was constructed in the remarkably short time of 16 months and completed on January 15, 1943 at an approximate cost of $83 million. It consolidated 17 buildings of the War Department and returned its investment within seven years.

Total Land Area (acres) 583 
Government Owned (acres) 296 
Purchased or Condemned (acres) 287 
Total Land Cost $2,245,000 
Area Covered by Pentagon Building (acres) 29 (34 including courtyard) 
Area of Center Courtyard (acres) 5 
Area of Heating and Refrigeration Plant (acres) 1 
Area of Sewage Structures (acres) 1 
Access Highways Built (miles) 30 
Overpasses and Bridges Built 21 
Parking Space (acres) 67 
Capacity (vehicles) 8,770 
Cost of Building $49,600,000 
Total Cost of Project (including outside facilities) $83,000,000 
Gross Floor Area (sq. ft.) 6,636,360 
Net Space for Offices, Concessions and Storage (sq. ft.) 3,705,793 
Cubic Contents (cu. ft.) 77,015,000 
Length of Each Outer Wall (ft.) 921 
Height of Building (ft.) 77' 3.5" 
Number of Floors, plus Mezzanine and Basement 5 
Total Length of Corridors (miles) 17.5

Building Proposed mid-July 1941 
Prime Contract Awarded 11 August 1941 
Mechanical Engineering Contract Awarded 3 September 1941 

Construction Began 11 September 1941 

Grading Contract Awarded 24 September 1941 

First Occupants Move in 29 April 1942 
Construction Completed 15 January 1943 
Sand & Gravel Used for Concrete (tons) 680,000 
Buildings Consolidated to Populate the Pentagon 17