History of the Pentagon
During the late 1930’s and early 1940’s the War Department consolidated its many
temporary and permanent offices scattered throughout the District, Maryland and Virginia.
The historic lands of the Washington, Custis and Lee families provided the necessary space.
The first project was the construction of Federal Building No.2, also known as the Defense
Department Arlington Annex and the “Naval Annex.” This building, located up the hill from the Pentagon,
had over one million square feet of space and a capacity for 7,000 employees and was originally occupied
by several divisions of the Navy. On the former Syphax property, Henderson Hall housed a barracks
and headquarters for the Marine Corps. The large acreage once occupied by Arlington Hall junior college
became a highly classified military post. Fort Myer’s south post was established on the former land of
the Arlington Experimental Farm, and the new War Department Building – ultimately known as the Pentagon – began construction.
The first site to be considered for the Pentagon’s massive building was the 200-acre tract of the Arlington Experimental Farm.
Scheduled to be turned over by the Department of Agriculture to the Arlington National Cemetery,
the National Capital Parks and Planning Commission and the Commission of Fine Arts wanted that area preserved for parks, the Cemetery expansion and an
unobstructed gateway to Washington, D.C. However, recently constructed bridges and highways provided great access, and the entire river lowland area
of Arlington between the Fourteenth Street Bridge and the National Cemetery came under extensive development pressure. When the relocation of the old
Washington Municipal Airport freed up its land, the five roads bordering the site confined the building to this shape.
While the final site had more flexibility, the building retained the original five-sided design.
As the sounds of war grew louder, Congress appropriated $35 million for construction of the War Building.
At the end of this period of Federal expansion, U.S. Government holdings accounted for 18% of Arlington County’s total geographic area.
The assignment to plan and build the new War Department building was given to General Brehon Somervell,
chief of construction in the Army’s Quartermaster Corps. Work began by moving six million cubic yards of earth
onto the site, and then sinking more than 41,000 concrete piles to stabilize the foundations.
Built entirely of concrete to conserve steel and faced with Indiana limestone, the building has
five sides and is three stories high. Working around the clock, a force of thirteen thousand workers
completed the construction in sixteen months.
The first occupants moved into the building in April 1942, and the building and
its outside facilities were finished in January 1943. Its interior traffic flows horizontally instead of vertically,
with elevators as found in high-rise office structures. Using its rings, radial corridors and escalators,
no two offices are more than 1,800 feet apart, about a 6.5 minute walk. The Pentagon is the world’s largest
office building, containing 6.5 million square feet of space. At the time of its heaviest use in World War II,
37,000 employees worked in the Pentagon.