The World Trade Center is a partially completed complex of buildings, under construction, in Lower Manhattan, New York City, United States, replacing an earlier complex of seven buildings with the same name on the same site. The original World Trade Center featured landmark twin towers, which opened on April 4, 1973, and were destroyed in the September 11 attacks of 2001, along with 7 World Trade Center. The other buildings in the complex were severely damaged by the collapse of the twin towers, and their ruins were eventually demolished. The site is being rebuilt with six new skyscrapers, a memorial to those killed in the attacks, and a transportation hub.