The World Trade Center is a mostly completed complex of buildings in Lower Manhattan, New York City, U.S., replacing the original seven buildings on the same site that were destroyed in the September 11 attacks. The site is being rebuilt with up to six new skyscrapers, four of which have been completed; a memorial and museum to those killed in the attacks; an elevated park adjacent to the site, called Liberty Park; and a transportation hub.[note 1] The 104-story One World Trade Center, the tallest building in the Western Hemisphere, is the lead building for the new complex.
The buildings are among many created by the World Trade Centers Association. The original World Trade Center featured the landmark Twin Towers, which opened in 1973, and were the tallest buildings in the world at the time of their completion. They were destroyed on the morning of September 11, 2001, when al-Qaeda-affiliated hijackers flew two Boeing 767 jets into the complex in a coordinated act of terrorism. The attacks on the World Trade Center killed 2,753 people. The resulting collapse of the World Trade Center caused structural failure in the surrounding buildings as well. The process of cleaning up and recovery at the World Trade Center site took eight months, after which rebuilding of the site commenced.
After years of delay and controversy, reconstruction at the World Trade Center site started. The new complex includes One World Trade Center, 3 World Trade Center, 4 World Trade Center, 7 World Trade Center, and one other high-rise office building being planned at 2 World Trade Center. The new World Trade Center complex also includes a museum and memorial, and a transportation hub building that is similar in size to Grand Central Terminal. 7 World Trade Center opened on May 23, 2006, making it the first of five skyscrapers to have been completed in the World Trade Center complex. 4 World Trade Center, the first building completed as part of the site’s master plan, opened on November 12, 2013. The National September 11 Memorial opened on September 11, 2011, while the Museum opened on May 21, 2014. One World Trade Center was opened on November 3, 2014. The World Trade Center Transportation Hub opened to the public on March 4, 2016, and 3 World Trade Center opened on June 11, 2018. 2 World Trade Center’s full construction was placed on hold in 2009, with a new design announced in 2015.