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).
List of tallest buildings in Shenzhen
Shenzhen, a major city and Special Economic Zone in Guangdong, China, is home to 1108 completed high-rises. The tallest building in Shenzhen is the Ping An Finance Centre, upon its topping out in 2015. It is also currently the fourth tallest in the world. The second and tallest fully completed building in the city is the Kingkey Finance Tower. The third tallest building is Shun Hing Square (otherwise known as the Diwang Building, 地王大厦), which stands with 69 stories. It was the tallest all-steel building in China at its completion in 1996. Shenzhen's high-rise building boom shows no signs of slowing down, with numerous proposals for skyscrapers taller than .