When was the Pentagon built?
The Pentagon
On the building's main concourse is the Hall of Heroes, opened 1968[57] and dedicated to the more than 3,460 recipients of the Medal of Honor, the United States' highest military decoration.[58][59][60][61]
[62][63] The three versions of the Medal of Honor–Army, Sea Service (for the Marine Corps, Navy, and Coast Guard), and Air Force–are on display along with the names of recipients.[62]
The Hall is also used for promotions, retirements, and other ceremonies.[64][65][66][67][68][69]