While most people rightly reflect on the WTC during 9/11, for me, it's the Pentagon
I worked there from 1987 to 1994 of the fifth floor, A Ring, which is the center most.
I've actually visited the WTC Observation Deck once on a day trip to NYC. It had spectacular views of the entire city. From that high up, everything, every other tall building and even the Statue of Liberty across the bay, looked small. But like I said, I had only been there once in my life.
At the Pentagon, I had worked there five days straight, for more than seven years. I knew all the floors and corridors, from the basement to the Center Court. Every day I'd head down to the Concourse book store or the cafeteria, the Library, or just roam the corridors during my lunch hour. I got to know the many civilians who worked there every day, from the maintenance and cleaning staff to the secretaries (I even dated one once).
I felt proud to work at the headquarters of the nation's defense, doing my regular Air Force job that I could do anywhere else in the world... But I was doing it at the Pentagon, where the people I served were generals, all the way down to low ranking airmen. And despite the fact that the place is full of brass, unless you had stars on your shoulder-boards, well, there's no point in getting a big head. I used to say that you could roll a bowling ball down any corridor and hit three or four colonels.
And pretty much the entire time I was there, the place was under massive renovation. Remember that the building was originally build during WWII and in many ways, it looks as if it hadn't changed since. So areas were refurbished, but many others weren't. The build inside was a mixture of old and new. Whenever I would see movies that supposedly depicted the Pentagon's interior, Dr. Strangelove for example, I knew that the real Pentagon was a lot more disappointing than the imaginary once. By the way, one area that I never entered during my time there was the NMCC, the National Military Command Center. Pretty much the place where you'd see in movies where people would be sitting at desks, looking at a wall full of screens. Now whether it actually look like that, I wouldn't tell you. However, the rest of the build is nothing more than what you'd find in any other government office build, but with people in uniforms walking around.
It was at the Pentagon where I became politicized. Reagan and Bush and Clinton after that. Listening to the local Pacifica station, WPFW, even at my desk while I worked. I started collecting books, I observed the inner workings of the Federal Government, I had many, many discussions about the sundry political matters of the day with just about anybody. For me, my time there was the greatest political education that I could ever have. I absorbed so very much about what and how things worked and didn't work. My time there cemented my impression of what America does and how it operated for the rest of my life.
It's because of my time there that had eventually brought me to DU.
And on that day nineteen years and one day ago, my greatest concern were for the people in the Pentagon when I had heard that it was also attacked. We were told that the airliner had skimmed the elevated Wash. Blvd next to the building, taking out street lamps before slamming into the outer wall near the old heliport location. That part of the building, which was directly around the corner from where I used to work, where I had been plenty of times for various reasons over the years, was caved in. Knowing how the windows were sealed, I imagined the smoked having nowhere the go, with those in that area who survived doing what they could to make their way through the smoke, darkness and rubble. Later I had found out that no Air Force personnel had died in the attack, but that was little comfort, because I had become acquainted with civilians and member of the other branches during my time there.
Again, the attack happened seven years after my own departure, but seeing the place in smoke on TV struck me like I had just been there the day before. If anything, the only saving grace was the fact the that airliner had smashed into a section of the building which just been recently renovated and thus, was relatively sparsely populated. At it were, aside from those on the plane, only 125 Pentagon workers were lost.
I was also relieved that the plane did not crash directly in the Center Court. Had it crashed there, much more of the building would have been destroyed and there would have been a much greater loss of life. As I said before, I used to work in the center ring. A crash would have pretty much killed everyone in that ring in a Center Court crash.
In the many years since I had left in 1994, I had never been back. I didn't want to bother going through the tour pass process for a place that I had the run of for seven years. I was sure that many of the people were long gone as well. I was content with leaving it in my past.
But every year around this time, my thoughts turn to the Pentagon and what it had gone through on that fateful day and all the live who were lost as well. I took that phase of the terrorist attack personally. And I still do to this day.
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May we never forget 
identify with The Pentagon since you worked there so long, and in service to Our Country! Thank you.
And just interesting to hear someone give a more detailed description of the physicality, and hustle bustle of the place; usually in TV, and movies it's short bits of hallway, then people walk into a room of various kinds. Plus your photos add more, too!
I'm a native NYC'r and spent almost a whole year about 18 years, and 49 weeks -Ago- to the 9-11 date in the South Tower (#2) on the 73rd Flr in a big open NE corner office.
Where I feel a link is you mentioning the Pentagon's Concourse - bookstore, cafeteria et al.
Below ground, and in between, and at the sides of the Twin Towers was a massive Concourse!
Cafes, food kiosks, drugstores, eyeglass places, banks, clothing shops, ice cream kiosk (Ben & Jerry's), doughnut shop, newspaper stands, at least one book store 🙂 and more.
I spent a lot of time there after work. And way after that because I worked in different parts of Lower Manhattan, I often picked up stuff after work since I could get so many different things I needed.
I hadn't thought about the Concourse yesterday ~ thanks for helping me remember. 
