Height: 1,368 and 1,362 feetOwners: Port Authority of New York and New Jersey
Architect: Minoru Yamasaki, Emery Roth and Sons consulting
Engineer: John Skilling and Leslie Robertson
Ground Breaking (when they started on the base): August 5, 1966
Opened: 1970-73; April 4, 1973 ribbon cutting
Destroyed: Terrorist attack, September 11, 2001
The World Trade Centers were main buildings in the United States
of America. They were some of the biggest towers in the world. They got
taken out by a terrorist attack on September 11, 2001. A tragic day in
history.
The World Trade Centers appeared to have no windows because of the metal beams on the outside that were only 22" apart. The buildings have 110 stories each. They mostly depended on those steel columns along the outside. The central core is supposed to only support the vertical loads. Then there are floors that go around the central core that are supposed to give it some help.
When the World Trade Centers got hit by the two planes though damage didn't look fatal. But it was when the planes hit the explosion weakened the columns on the outside. The fire blew up into the upper floors which weakened all of those floors. Eventually the top floors had to give and when they did the momentum from those top floors falling down brought down the rest of the building.
There is a different story with the South Tower.
The North tower collapsed directly down on itself. Unlike the South Tower
which the floor that the plane hit, eventually blew out, and that made
the floors above collapse sideways. The top floors hit the floors below
it and made the rest of the building fall down.
| Hindenburg | Hugo |
| Twin Towers | Depression |
| Mount St. Helens | Games |