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At 553.33 meters (1,815.39 feet), Canada's National Tower is the world's tallest free-standing structure on land. The CN Tower is located in the city of Toronto, Ontario, Canada and is considered the signature icon of the city which attracts over 2 million visitors yearly.
Built in 1976 by Canadian National Railway (CN) to demonstrate the strength of Canadian industry, the tower was originally designed as a radio and television transmitting antenna. There are microwave receivers for distant signals at about 305 meters, and the top of the transmission antenna is at the apex of the tower. However, CN soon found it was far more lucrative as a tourist attraction. With over a million tourists climbing the tower each year it has yet to have an unprofitable year. The construction costs were repaid in fifteen years.
Metal staircases with 1776 steps reach the Skypod level (447 m) and are the tallest metal staircase on earth. These stairs, intended for emergency use, are used twice yearly for charity stairclimb events by the United Way's Toronto chapter. The average climber takes approximately 30 minutes to climb to the base of the Raydome (the white bubble on the bottom of the main pod), but the fastest climb on record is 7 minutes 58 seconds.
CN is the official acronym of the former Canadian National Railway, but following the railway's decision to divest non-core freight railway assets during the lead-up to the company's privatization in 1995, the CN Tower was transferred to the Canada Lands Company (CLC), a federal Crown corporation responsible for real estate development. Since the citizens of Toronto wished to retain the name CN Tower, the acronym CN now stands for Canada's National rather than the original Canadian National.
From 1997-January 2004, TrizecHahn Corporation managed the building and instituted several expansion projects including a $26 million entertainment expansion and revitalization that included the addition of two new elevators (to a total of six) and the relocation of the staircase from the cityside (north side) shaft to inside the core of the building.
At 342 m is the Glass Floor and Outdoor Observation Deck, at 346 m are Horizons Cafe and the Indoor Observation Deck, and at 351 m is the 360 Restaurant, which rotates once every 72 minutes. The restaurant has a minimum purchase requirement and a vast menu.
The Sky Pod, a small enclosed platform elevated high above the main observation floor, is located at 447 m, and is the highest public observation deck in the world. Admission to the Sky Pod requires payment of an extra charge.
In 1995, the CN Tower was declared one of the modern Seven Wonders of the World by the American Society of Civil Engineers. It also belongs to the World Federation of Great Towers. The following year, the Guinness Book of World Records officially changed the CN Tower's classification to "World's Tallest Building and Free-Standing Structure".
There are many guyed towers taller than the CN Tower, the current tallest being the KVLY-TV tower in North Dakota at 628 m (2,063 feet) tall (see List of masts), but these are guy-wire supported structures and not classified as free-standing. The Petronius Compliant Tower (an oil platform) at 645 m (2,116 feet), is a taller free-standing structure, however all but its top is under water. If built, a 1,000 m tower for a solarthermic power station in Australia will break the record. The Burj Dubai, slated for completion in 2008, would according to present claims by its developers, become a taller free-standing land structure than CN Tower. See World's tallest structures for further analysis of the tallest man-made structures.
The builders of the CN Tower did not expect that it would hold the tallest structure record for so many years. Previous record holders had quickly been supplanted. Several rivals have been proposed and designed but none have yet been built and most schemes collapsed. In part this is because of the development of cable television soon after the tower was built which greatly reduced the need for such broadcasting centres, especially in urban areas. Only in cities, however, are there enough tourists to make such a tower viable as a tourist attraction.
On July 23, 1999 Ashrita Furman became the fastest person to go up the CN Tower using a Pogo stick. In 2001, a group of environmentalists scaled the tower to place a banner protesting the policies of President Bush on the tower.
- Official site of the CN tower
- Guinness entry for the CN Tower
- What is the tallest building in the world?
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