Although they were called "twins," the Twin Towers differed slightly in height, with one standing 1,368 feet tall and the other rising only to 1,362 feet tall, according to Skyscraper.org. Each building had 110 stories.
The two towers served as the symbols of the World Trade Center, but five other buildings helped complete the complex owned by the Port Authority of New York and New Jersey. Tower One was completed in 1972, and Tower Two was completed in 1973. At that point, they were the tallest buildings in the world for a short time. The Sears Tower became the tallest building in 1974. The towers were destroyed in the terrorist attack on the United States on Sept. 11, 2001.