United Airlines Flight 175

The original World Trade Center (WTC) was a complex of seven buildings in the Financial District of Lower Manhattan in New York City. Built primarily between 1966 and 1975, it was dedicated on April 4, 1973, and was destroyed on September 11, 2001 after two hijacked planes were flown into the towers in a coordinated terrorist attack. The complex included the 110-story-tall Twin Towers, at the time of their completion the tallest buildings in the world, with the original 1 World Trade Center at 1,368 feet (417 m), and 2 World Trade Center at 1,362 feet (415.1 m); they were also the tallest twin skyscrapers in the world until 1996, when the Petronas Towers opened in Kuala Lumpur, Malaysia. The other buildings in the complex were the Marriott World Trade Center (3 WTC), 4 WTC, 5 WTC, 6 WTC, and 7 WTC. The complex contained 13,400,000 square feet (1,240,000 m2) of office space and, prior to its completion, was projected to accommodate an estimated 130,000 people.

9/11 hijacked passenger flight, hit the South Tower of the World Trade Center