@trelleville: 1. The Pentagon is the headquarters of the United States Dept. of Defense and the world’s largest office building. 2. It covers an area of nearly 6 million square feet and houses nearly 23,000 employees. 3. It has 17.5 miles of hallways and 28 elevators. 4. It has 5 floors and 5 concentric pentagons - hence its name. 5. It has a mote surrounding it that is almost 2 miles in circumference. 6. It contains a cafeteria, an indoor gymnasium, an auditorium, and the Pentagon 9/11 Memorial. 7. It is the only pentagon in the world that is specifically used for military purposes.