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 Toronto
The most prominent landmark in Toronto, and its best known symbol, is the CN Tower. It was the world's tallest free-standing structure for 31 years, from its completion in 1975 until Burj Khalifa in Dubai, United Arab Emirates surpassed it in 2007; it remains the tallest free-standing "tower" in the Western Hemisphere. The CN Tower is used as an observation tower, as well as a communications tower. Another landmark structure is Casa Loma. Constructed by E. J. Lennox during the early 1910s, it is a Gothic revival-style castle located on Walmer and Davenport roads. It was originally the residence of Sir Henry Pellatt, a Canadian financier and soldier. The city later took over the castle when Pellatt could no longer afford to keep it. The building presently operates as a museum.