. It was attacked September 11,2001.The Pentagon is a symbol of the U.S.A. Did you know that construction was during World War 2.It has 5 wedge shapes. It’s also a National Historic Landmark. It’s a very strong building. The U.S. Capitol could fit into any one of It’s 5 wedge shapes. The Pentagon is located in Arlington VA. It’s the Headquarters of Department of Defense. George Bergstrom designed it.189 people died during the attack September 11,2001.They built it out of concrete.