The Pentagon is one of the most unique and coolest buildings in the world – there is nothing quite like it. Over 25,000 people work in the Pentagon, a mixture of military personnel, contractors and civilians. Sept. 11, 1941 construction began, and Sept. 11, 2001 is when the a hijacked plane crashed into the Pentagon – so September 11 is a very important date.

Discover 15 Very Cool and Interesting Facts About The Pentagon

1. The Pentagon was designed by George Edwin Bergstrom.

2. It is the headquarters for the U.S. Department of Defense.

3. The Pentagon is located in Arlington County, Virginia across the river from Washington. Many people think it is located in Washington DC.

4. The Pentagon is the headquartered of the United States Armed Forces: Air Force, Navy, Coast Guard the Army and other branches.

6. The Pentagon is five-sided because the original site of the project (Arlington Farms) was pentagon shaped. So when engineers moved construction to another site as ordered by President Franklin Roosevelt, where the building is today – Hoover field, the shape of the building could not be changed because the planning stage was too far ahead.


7. Construction began on September 11, 1941 and the projected was fully completed on January 15, 1943.

8. The Pentagon is built mostly using concrete because steel was in short supply thanks to World War 2. Therefore the building is short but over a wide area. Steel is needed to build high.

9. The project cost an estimated 1.11 billion dollars US.

10. It was built during Franklin D. Roosevelt‘s presidency; he was very involved and had a massive influence on the entire project.

11. The Pentagon is 71 feet tall (22 metres) and has 7 floors. It is 6,636,360 square feet or 620,000 m2 – making it the largest office building in the world.

12. The Pentagon has over 280 bathrooms.

13. Even though it is a very large building, it was built very fast thanks to a 24 hours a day construction schedule (with over 15,000 workers). The main contractor John McShain, Inc was under a lot of pressure from the US government to build quickly.

14. Apartments were built onsite for managers, supervisors and other contractors.

15. On 9/11 (11 September 2001), the Pentagon suffered massive damage from the hijacked American Airlines Flight 77. It was hijacked by terrorists who crashed the plane on the west side of the building – in total, 189 people died.