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).
Architecture of New York City
The Empire State Building, a 102-story contemporary Art Deco style building, was designed by Shreve, Lamb and Harmon and finished in 1931. It was the world's tallest building for a record 42 years. The tower takes its name from the nickname of New York State and is currently the third tallest building in the city, the first being One World Trade Center, and second belonging to 432 Park Avenue. It was the first building to go beyond the 100+ story mark, and has one of the world's most visited observation decks, which over 110 million have visited since its completion. The building was built in a record 14 months.