World Trade Center
Although there are many other buildings and complexes both in the United States and around the world named the World Trade Center, the steel tube building skyscrapers of the "Twin Towers" and the complex surrounding them, build by the Port Authority of New York and New Jersey in 1970 at a cost of $400,000,000, were by far the best known edifices of that name.
When the towers were completed in 1973, they were the tallest buildings in the world. At the time of their destruction on September 11, 2001, they were the fifth tallest.
The towers were not universally beloved at the outset. For one thing, they displaced a neighbourhood of small business and a few residents known as Radio Row, thereby changing the character of lower Manhattan. Their design was unappealing to some; detractors called them Lego blocks or Block City. However, by the turn of the millennium, many younger residents of New York City could not recall the skyline without them, and they were universally accepted as a representative icon of the “Big Apple”.
There were several incidents at the towers. In 1974 French daredevil Philippe Petit walked a tightrope strung between the towers, and in 1975 a fire did serious damage to the north tower, although there was no loss of life and no structural damage to the tower.
The towers were attacked twice, once by the World Trade Center 1993 bombing, which killed six persons and injured over 1,000. The 9-11 attacks destroyed the towers and damaged the rest of the World Trade Center complex beyond repair. Over 3,000 persons were killed. The center will be rebuilt, with a new skyscraper, the Freedom Tower, and a permanent memorial.
-  - a PBS site with WTC facts