Why the Pentagon is a pentagon

It's pentagon time!

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[Irrelevantmaddy]

They also didn't include elevators because they wanted to conserve steel and iron for ongoing war efforts. This is also why the original structure was made of reinforced concrete. I'm a Pentagon Tour Guide, I love seeing these videos!

[HerbertLandei]

Originally, it was planned as an octagon, but they had to cut corners.

[unclewoobie]

My dad loves to tell a story about his grandfather being one of the plaster contractors to build the pentagon. He watched someone get fired for filling in doorways and plastering over them so they wouldn’t have to plaster that room, saving time or money I guess. They thought nobody would notice that entire rooms were missing from the floor plan. My great grandfather had to figure out where the rooms were, and complete the job the other contractor botched.

[colinpovey]

I grew up about 2 miles from the Pentagon. And I worked in it as a contractor for about 3 months, installing computer gear, before PC's existed.
My mom was a secretary in the Pentagon when it only had 3 sides. No joke. They were so desperate for office space, they started working in the building before it was complete.

When the Pentagon first opened, busses from DC were not allowed to cross into Virginia, so workers were dropped on the DC side of the Potomac river, and had to walk across the river and to the Pentagon, with zero regard for the weather. President Roosevelt issued an order allowing the busses into Virginia for the duration of the war, in the name of efficiency, and in reducing the number of sick days workers took.

The story goes that the military figured they would need lots of space for records after the war, so the Pentagon was designed as a records retention building/library, meaning it is stronger than a regular office building (paper records weigh a lot more than people). Helped it survive 9/11 attack.


Lots of people ride 3-wheel bikes in the Pentagon. Plumbers, electricians, telephone repair, etc.Really very efficient.
The Pentagon has (at least) 5 ZIP codes. Each branch of the service has one, as well as one for the DOD. Not sure about Space Force.
There are about 17 restaurant/cafeteria's in the Pentagon. At least one is always open.
There is a small shopping center in the Pentagon. Not only department stores, but uniform stores, other clothing, drug stores, shoes, shoe repair, barbers, hair salons, etc.

9/11 Pentagon trivia. The Pentagon is in Arlington, Virginia (evidence is you pay Arlington sales tax). So Arlington Fire Departments handles fires there.
Well, on 9/11, they ran into a problem. They needed to get a ladder truck into the courtyard, to get firemen on the roof attacking from that side.
But the courtyard, which was originally mostly grass, had been paved over, multiple times, and this made the one road into the courtyard higher than it was designed, and they could not get a ladder truck inside! So, in the end, they did two things. Arlington FD took a metal cutting chain saw and removed the driving position on the read of the ladder truck, just cut it off! Second, the Arlington FD called around to small area fire departments, and in one found a nearly 50 year old ladder truck, the reserve ladder truck in a rural Maryland area, and had them send that down, because it was short enough to get inside the courtyard, but it's ladder was just long enough to get fire fighter onto the roof.

Lastly, the location was the original location for Hoover field, the first airport in the DC area. It was too small for a real airport anymore, so they built the larger National Airport just about a mile down the river, on a land fill area in the river

Phew!.

[navyaustin]

Good video - some comments to amplify:
- Those old army buildings on the Mall were a very common Federal style - long wide front with wings coming out perpendicular, sort of like a comb. Those wings typically had a center hall and 20-30 foot bays either side. Lots of light and ventilation, very important pre-AC. The old Navy Annex up the hill (now razed) was like that.
- That Federal style runs into limits - a LONG way from the farthest wings. One early design to fit the shape basically had 5 of those buildings with wings going in. Instead, they made the rings - It’s really like 5 concentric pentagons, with windows and space in between. Some parts on the ground floor go all the way across, but above the 3rd floor, you walk indoor sky bridges between wings.
- I remember 1 escalator going up when I was there in 92, in the A ring. The renovation put escalators at each of the A-ring apexes, Nice and airy. There are also elevators on each of the 10 main corridors at around the D Ring.
- Tricycle carts for delivery or building maintenance still used, as are electric carts. Far fewer than there used to be, because inter office mail has been replaced by email. Much less movement of physical paper from office to office. There are ramps so they can move from floor to floor.
- In the 40s and 50s, city busses came into center court and dropped passengers. There is a Metro station and bus terminal at the Pentagon. You used to be able to go from Pentagon to Metro in the building, there’s an air gap now - exit the building, walk under a covered walkway, escalator down to Metro.
- The building had a ground floor and four floors above that. Almost immediately, a 5th floor was added - narrower halls, shorter ceilings. The renovation made the 5th floor a regular floor with the same dimensions as the others.
- The BestBuy is now an AAFES uniform store. Other retailers include a jewelry store, flower shop, gift shop, Bank of America and Navy Federal Credit Union branch, barber shop, beauty salon, dentist, Virginia DMV service desk, optical shop, chocolate shop. Some spaces are for temporary concessionaires - trunk sale clothing, holiday/seasonal.
- There are also convenience stores - Blind Operated Businesses. And a full CVS.
- The center court grill, aka Ground Zero, was under renovation last time I was there. They built a really nice indoor food court with lots of the usual fast food places. There’s also a pay by weight food bar (salad bar, pasta bar, etc.) And some other places to eat throughout.
- The gym, once called the Pentagon Officers Athletic Club, now the Pentagon Athletic Club, is really nice. One boss advised newcomers to get to the gym - turns one long shitty day into two short shitty days! Interesting to see the generational shift - racquetball and squash courts being converted to CrossFit boxes.
- The renovations were a to the cement gutting, one wedge at a time. It had been built before computers and their increased electric, AC, and network cable needs. They modernized all of that. Also added Kevlar in exterior walls and the glass was thick laminated, like an inch thick. Laminated for blast protection, thick to thwart using a laser mic to listen in on conversations from a distance. The plane hit one of the renovated wedges, which prevented a lot of injuries from flying glass and shrapnel.
- Friends who worked in the building on B-ring 4th deck could see the exit point of the plane and the engine that came to rest in the space between B and C rings. The Navy command center was one of the hardest hit.
Stationed there 3x, 92-93, 09-12, 16-19. Saw the changes from the big modernization. Unlike many, I loved it - always felt like an exciting place to be, and kind of homey at the same time.

[KeithHearnPlus]

It's worth noting that the officer in charge of the construction of the Pentagon, who made a building out of all that chaos, was Colonel Leslie Groves, who was promoted to General when he took charge of his next project, codenamed "Manhattan".

[brynmerrett]

It is apparently one of the hardest buildings to navigate due to every corridor looking the same as the one you just left. Having 5 floors above and 2 below ground with 5 rings of corridors A-E resulting in around 17 miles of corridor

[Arkelk]

The number of toilets is the happy result of a bad government policy: segregation. (President Woodrow Wilson ordered the federal government to be segregated ). In addition to the usual male and female facilities, and officer and enlisted facilities, there were colored and white facilities. When segregation thankfully went away, there were more toilets available for all. It's actually one of the nice things about working in that building.

[OneMo]

I'm happy to see the huge improvements you've been doing Phil, especially in the last few months. The quality is on another level. It feels like it has a Vox journalistic theme now. Keep up the good work.

[maxwillson]

I remember being in 4th grade when 9/11 happened and our teacher explained what the Pentagon was and I couldn't help but think, "well that's random." Our teacher was correct that I would remember that day for the rest of my life but it was because I learned we had a weird building that was in the shape as a Pentagon ahahaha, I know it's not a day to laugh about but that's my memory of 9/11.

[JKSSubstandard]

Im an architect who never heard this story...im frankly shocked given the militarys need for symbolism and tradition that it WASNT designed to invoke a star fort.

[erictaylor]

I read an article that was all about absurd military decisions. One such decision was the USSR's choice to select a hotdog stand as a primary target for it's nuclear war plans.
The thing the article did not mention was the location of this particular hotdog stand. It stood in the center of the courtyard of the Pentagon.
So while it might seem absurd to target a hotdog, it makes a lot more sense to target the center of the courtyard of the headquarters of the US Military. It just so happens that a hotdog stand is in that location. Because even Generals and Admirals need to eat lunch.

[RichardPhister]

I remember flying into Reagan National, seeing the pentagon from the air with no notion of the true size of it, thinking "oh it's not so big." Fast forward to staying at the Hilton right across from it, seeing it from the ground for the first time, and all I could say was "shit that's a big ass building."

[RAMStrands]

Thank you for keeping it clean and not adding in offensive humor. My 12 year old son and I just watched your video so we could learn more about the Pentagon.

[alexfrbnks]

My grandfather was one of the first residents of the pentagon and went on to work for the redstone arsenal and I believe my grandmother worked there as well doing work on the enigma decoder machine.

[craignunley]

I used to think the shape had something to do with the pentagon-shaped space created in the center of the stars that a five-star officer wears. But, it turns out that the five-star rank was created after the building was designed, so this is not the case.

[corgi_dad]

I find it interesting how the name of the building is just it's shape. If you see the word "Pentagon" you immediately think of that building. Also, somewhere I remember seeing a video of a kids toy like that where all of the pieces could be turned to fit through one hole.

[lsdzheeusi]

Even more important than the exact shape was the cultural message sent by civilian leadership: all branches of service were to work together toward the common goals. The shape and deliberate choice to facilitate interaction sent a powerful message.

Inter service rivalry is simply a fact of life and it’s unrealistic to expect frictionless relationships. With that said, just as an example during the Second World War, the Japanese Army and Navy were openly at odds much of the time, to the degree that the rivalry was more effective at stopping them from achieving their goals than allied military action. Likewise, the power struggles between the various German armed force cost them dearly.

Whereas the leadership of other countries may have seen some value in keeping various military factions at odds to ensure balance of power, this had a negative effect on their war fighting ability. In the US, squabbling military leaders had to share the same building, and location dictated that compromise could be forced.

It’s pretty hard to duck a rival when their office is in the same building!

[beefymcskillet]

One of my co workers carry’s a pice of metal with him every day. That piece of metal was part of the plane that hit the pentagon. It reminds him that even though he’s having a bad day somebody had a worse day

[thinkfact]

Wonderful video Phil, now I'm checking out your other stuff and finding myself subscribing! I think what's most refreshing is your ability to say a lot in a short amount of time. I feel one of the big holes a lot of people who make informative videos can get themselves into is making videos that become longer and longer and longer. That's not a bad thing, but I always find it refreshing to find these short and sweet little tidbits. Keep up the great work!