The pentagon is without a doubt one of the most famous buildings in the world that are still in use today. While Australia has the Sydney Opera House, and Dubai has the Burj Khalifa, London has Big Ben, America has the Empire State Building and the Pentagon. The Pentagon is famous for its use as the center of defense for the US government, for its strange shape, and for the tragic terrorist attack that took place on September 11th. So why is the Pentagon a pentagon?
To understand the logic you need to understand the time that it was built. The building started construction in 1941. Hitler was ravaging Europe at the time and it was becoming clear that America would soon enter the war. This meant that there was a serious need for the defense department to be located in one building instead of the 70 they were located in, prior to the construction of the Pentagon. It also meant that steel was in short supply as it was being used to build more weapons. This building would have to be made from something else.
The Department of defense purchased a five-sided piece of land and tasked architects to come up with a design that would maximize this space. They drew up the designs of the Pentagon. Soon there were objections in place as the large building would block views of the vistas of Washington from the nearby cemetery. President Roosevelt took the opportunity to move the building site to a nearby slum that needed to be eradicated. Eviction notices were served, buildings were demolished and the new site of the Pentagon was found.
This, of course, meant that the Pentagon shape was no longer required however the design team lobbied hard to keep it. They felt that the concentric rings of buildings tied together with corridors allowed people to move around far easier than if a circle or square building was used. The lack of steel meant that the building could still not be very high and the river nearby meant that it could not go above four stories or it would block the river view. After some lengthy debate, the pentagon Pentagon design was approved.
Since its construction, it has never actually been able to house the entire Defense Department. Although every president since the Cold war has reduced the budget and made the department smaller, Trump is now making it larger, so it appears that it will never fit it either.
On September 11th, 2001, American Airlines Flight 77 crashed into the pentagon and killed 184 people including the five hijackers, 59 other passengers, and 120 Pentagon employees. The building was undergoing renovations at the time and had been for 17 years. The renovation continued after as the damage from the crash impacted three of the outer concentric pentagons. Workers returned to the offices in August 2002.
The halls are so long that during World War 2 employees were allowed to use bicycles and roller skates to get from office to office across the Pentagon. As time went on small electric vehicles were added to the hallways. However, these were very dangerous and caused numerous accidents. Today only those who require electric scooters are allowed to use them. Everyone else gets a little exercise.
There are many theories of underground bunkers beneath the Pentagon however these can be quickly disproven. For years the building was open to the public and the interior courtyard was a very popular lunch spot. The theory that the courtyard served as an entrance to an underground bunker can be quickly dismissed.