series of airline hijackings and suicide attacks committed in 2001

To take over the planes, the hijackers smuggled box-cutters and knives through security.

1.5 million working hours during 261 days were spent removing the debris at the WTC Site

The ages of the nearly 3,000 victims ranged from two to 85 years old. About 75-80% of the victims were men.

 After the tragedy, there was a three-day flight ban over the United States.

The attacks were precipitated in large part because Osama bin Laden

While workers were going through the debris

they found 65,000 items, including 437 watches and 144 wedding rings.