The Pentagon The Pentagon is an United States Department of Defense in Washington D.C, or Arlington Virginia.It was built so the Department would become more organized, with the World War II going on. Now, the Pentagon is currently being used for the United State’s Department of Defense. The Pentagon includes all four branches of the military, (the marine course, navy, army, and the air force). It’s construction began on September 11, 1941 during the World War II, and was finished on January 15, 1973. The Pentagon took 16 months to build, with 13,000 builders, which costed 1.1 billion dollars. The builders used 41,492 concrete pilings to make the foundation, and 435,000 cubic yards of concrete. The builders used 680,000 tons of sand and gravel for the concrete. It has a total floor area of 6.6 million square feet, one of the world’s largest office buildings. It stands five stories tall, which is 77 feet high, and two below-ground levels, labeled the basement. The Pentagon has 5 concentric rings labeled A, B, C, D, and E. The basement ring segments are labeled F and G. The E ring has the only offices that has windows for outside view. The second floor of the Pentagon is called the concourse, a mini-shopping mall. …show more content…
A pentagon is a geometric figure with 5 straight sides and 5 equal angles. Each interior angle of a pentagon measures 72°, and each exterior angle of a pentagon measures 108° degrees. Some interesting facts about the Pentagon are that it has 131 stairways, 284 washrooms, 4,200 clocks, 19 escalators, and 691 water