No it wasn't seen before they collapsed, it was seen and photographed just after they collapsed.
No. They only collapsed once, on September 11,2001
The towers were completed in 1972, and collapsed in 2001 - 29 years.
The south tower of the World Trade Center collapsed at 9:59am. The north tower collapsed at 10:28am.
The South Tower Collapsed at 9:03am and the North Tower Collapsed at 9:28am
Trying to leave New York, his 30th Anniversary concert was Madison Square Garden the night before the attacks.
Yes. The twin towers collapsed in September 2001.
Oh, yes. Almost 3000 people died b/c of the attack on the Towers.
When they collapsed, all that was left was rubble which was cleared up - it couldn't be salvaged.
No. The world trade center collapsed due to the weakening of the interior structure of the towers
Some people had families that were in the twin tower when it had collapsed
The defences of a concentric castle were round towers - It was harder for attackers to make round towers collapse. Unlike square towers they had no corners, which collapsed if holes were dug underneath the foundations.
yes by crashing planes into the towers then they collapsed