The Twin Towers of the World Trade Center stood on this downtown spot from 1973 until the morning of September 11, 2001, when two hijacked planes were flown into them, causing their collapse and killing 2 973 people. After numerous projects, the site is now home to the new World Trade Center complex, made up of six office towers. At its foot, the poignant 9/11 Museum and Memorial commemorates the tragedy.