CN Tower
"Guinness World Records" has called the CN Tower "the world's tallest self-supporting tower" and "the world's tallest free-standing tower". Although Guinness did list this description of the CN Tower under the heading "tallest building" at least once, it has also listed it under "tallest tower", omitting it from its list of "tallest buildings." In 1996, Guinness changed the tower's classification to "World's Tallest Building and Freestanding Structure". Emporis and the Council on Tall Buildings and Urban Habitat both listed the CN Tower as the world's tallest free-standing structure on land, and specifically state that the CN Tower is not a true building, thereby awarding the title of world's tallest building to Taipei 101, which is shorter than the CN Tower. The issue of what was tallest became moot when Burj Khalifa, then under construction, exceeded the height of the CN Tower in 2007 (see below).
New York City
Manhattan's skyline, with its many skyscrapers, is universally recognized, and the city has been home to several of the tallest buildings in the world. , New York City had 5,937 high-rise buildings, of which 550 completed structures were at least high, both second in the world after Hong Kong, with over 50 completed skyscrapers taller than. These include the Woolworth Building, an early example of Gothic Revival architecture in skyscraper design, built with massively scaled Gothic detailing; completed in 1913, for 17 years it was the world's tallest building.