Ten years ago, on September 11, 2001, two airliners hijacked by terrorists crashed into the Twin Towers in New York, causing them to collapse to the ground and causing the death of 2,749 people. At 8.46 that morning the first plane hit the North Tower. 102 minutes later only rubble remains of the World Trade Center. Alberto Angela tells what happened inside the towers in those 102 minutes. There were many people working in the various offices, there were also tourists who, like every day, reached the observation point on the 110th floor. What were the reactions of those inside? Let's listen to some testimonies of those who were saved. Many managed to save themselves, others understood that they were trapped and that there was no way out. The dramatic images of that day, broadcast by television all over the world, have remained forever imprinted in our memories. Among the many images there is a shocking one, which has almost become the symbol of that tragedy.