Inside Twin Tower's Structure and the 911 Attack - Original World Trade Center

You answered more questions in 4 minutes than nearly any other full-length documentary I’ve seen about 9/11.

I’ll never forget this day! I was in 2nd grade and my elementary school was on 77th street in Manhattan. I was 10 minute drive from the towers! I just remember my name being called on the loudspeaker telling me to go to the main office. My dad picked me and my sister up. I’ll never forget seeing both towers on fire while driving uptown. My grandfather worked in the tower and he overslept that day and didn’t go to work. We were all blessed to be alive still.

This high quality video finally answered two important questions. 1 Why they collapsed. 2 Why people trapped in the upper floors never had a chance to escape. I can still visualize the second Boeing hitting the south tower.

22 years later & I still can’t believe this happened 😢 rest in peace to all

The smartest man was in the second tower who insisted his office evacuate, even though they hadn't been hit...that guy needs more press.

My greatest fear is hanging out of a window on the 105th floor and slipping or getting pushed out of the window. My biggest fear is falling from heights. I've had nightmares of this.

It took 20 years for me to understand how this happened unbelievable. You explained it perfectly

I was 35 when this happened. I wept on and off for two weeks following the attacks. The shock of it all, changed me forever. A profound sadness that only those old enough to understand the enormity of what happened that day can understand.

The story with the third staircase in the South Tower is sad. Even though it wasn’t blocked - it had some debris and flames in it that made it look blocked/dangerous to most people. Only 5 people managed to realize it was still passable (one of them actually called the police & told them about it twice before the collapse, but in the chaos the information got lost). The other survivors who managed to survive above the impact zone were in the Skylobby, which was directly where the plane hit. So it was below where the stairs falsely appeared blocked. There were hundreds of people in the lobby, and 14 who survived the plane hitting & were uninjured enough to move managed to escape.

I have watched many videos about what happened physically to the Towers upon impact, and I gotta say this is the first time I saw a clear and concise illustration that helped me to visualize accurately. You answered all the questions I ever had. Thanks much for this video

It's important to note the steel columns didn't "melt" but instead were weakened by the prolonged, intense heat from the fires, and thus lost their strength and ability to support the massive building-sized weight above them. Once the building-sized weight above the weakened columns dropped onto the main building below, the massive inertia force was unstoppable, and the building floors pancaked all the way to the ground. Nice job on the video.

Thank you for showing this and describing it. I always wondered what these building looked like and where the stairwells and elevators were.

You gave a clear explanation of what happened to the buildings, and why one of the stairwells in the South tower remained available. Thank you!

Nice presentation! One correction 3:43 There's actually no evidence of any steel columns melting; they were heated very hot & weakened substantially, but did not melt.

As others have said, you answered the main questions about the integrity of the building and in a very concise way. Many people don't realize there was an intact stairwell in the South Tower that could have been used to escape. It's sad that more survivors above the impact zone didn't realize this. I'm only one, but have subscribed - they all add up.

This is as much info as I’ve gotten from 10 other video’s separate, thank you for explaining so well

Awesome video. I don’t even know how I found this but I’m glad I did. Loved the diagram showing how the stairwells were cutoff and how the building steel melted. Excellent video.

This is the most amazing and enlightening presentation of what happened to the structures. Thank you for making this. You are very talented.

I will never forget still having to go to a luncheon work meeting that day when we knew we were under a terrorist attack and didn't know what else was to happen. On my way home from work that day I was still in shock and saw people just behaving normally, mowing grass, jogging etc and I couldn't understand it. I cried for at least 3 months straight. TY for explaining this.

Sadly, with one stairwell open the people above the impact zone thought they were trapped when they really weren’t. A few survivors made it past the impact zone. And one firefighter went up the stairs past the impact zone.