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{{About|the CN Tower in Toronto|the tower in Edmonton|CN Tower (Edmonton)}}
{{pp-move-indef}}
{{Refimprove|date=February 2010}}
{{Infobox skyscraper
|building_name = CN Tower
|image = ] Toronto's CN Tower.
|constructed = 1973–1976
|use = observation, telecommunications, attraction
|caption = <small> CN Tower is the ].</small><ref></ref>
|location = ], ], ]
|coordinates = {{Coord|43.6426|-79.3871|region:CA-ON_type:landmark|display=inline,title}}
|antenna_spire = {{convert|553.33|m|ft|1|abbr=on}}
|roof = {{convert|457.2|m|ft|1|abbr=on}}
|top_floor = {{convert|446.5|m|ft|1|abbr=on}}
|floor_count = 147 (equivalent)
|elevator_count = 6
|architect = ] Architects in association with ]
|skyscraperpage_id = 21
|emporis_id = 112537
}}
The '''CN Tower''', located in ], ], ], is a communications and observation ] standing {{convert|553.3|m|ft|abbr=off}} tall.<ref name="CNTower">{{cite web|url=http://www.cntower.ca/portal/GetPage.aspx?at=848|title=CN Tower web site|accessdate=2007-09-26| archiveurl = http://web.archive.org/web/20070723015815/http://www.cntower.ca/portal/GetPage.aspx?at=848| archivedate = July 23, 2007}}</ref> It surpassed the height of the ] becoming the ] in the world for the next 31 years.

On September 12, 2007 the CN Tower was surpassed in height by ] (formerly known as Burj Dubai).<ref name="CBCSurpassed">{{cite news |title= CN Tower dethroned by Dubai building|url= http://www.cbc.ca/canada/story/2007/09/12/cntower-surpassed.html|work= ]|publisher= ]|date= 2007-09-12|accessdate=2008-04-09 }}</ref> It remains the tallest free-standing structure in the ], the signature icon of Toronto's skyline, and a symbol of Canada,<ref>, The Torontoist, September 4, 2007. (retrieved on November 17, 2008).</ref><ref>, Broadcast News/canada.com, June 26, 2006</ref> attracting more than two million international visitors annually.<ref name="FACTS">{{cite journal|title=Facts at a Glance |url=http://www.cntower.ca/portal/Secure/Community/417/Documents/PressKit2005/2005%20Facts%20at%20a%20Glance.pdf|format=]|publisher=CN Tower|year=2005}}</ref>

''CN'' originally referred to ], the railway company that built the tower. Following the railway's decision to ] non-core freight railway assets, prior to the company's ] in 1995 it transferred the tower to the ], a federal ] responsible for ] development. Since local residents wished to retain the name ''CN Tower'', the abbreviation is now said to expand to '''Canada's National Tower''' rather than the original '''Canadian National Tower'''; however, neither of these names is commonly used.<ref name="CN">{{cite web
|url=http://www.cntower.ca/portal/GetPage.aspx?at=848#The%20Tower
|title= Canada's Wonder of the World
|work=CN Tower: Plan Your Visit > Who We Are
|publisher= CN Tower&nbsp;— Canada Lands Company
}}</ref>

In 1995, the CN Tower was declared one of the modern Seven ] by the ]. It also belongs to the ], where it holds second-place ranking.

==History==
]
].]]
The idea of the CN Tower originated from the 1968 ] had a desire to build a large TV and radio communication platform to serve the Toronto area, as well as demonstrate the strength of Canadian industry and CN in particular. These plans evolved over the next few years, and the project became official in 1972. The tower would have been part of Metro Centre (see ]), a large development south of ] on the Railway Lands, a large railway switching yard that was being made redundant by newer yards outside the city. Key project team members were NCK Engineering as structural engineer; ]; Webb, Zerafa, Menkes, Housden Architects; Foundation Building Construction; and Canron (Eastern Structural Division).

At the time, Toronto was a boom town, and the late 1960s and early 1970s had seen the construction of numerous large ]s in the downtown core, most notably ]. This made broadcasting into the downtown area very difficult due to reflections off the buildings. The only solution was to raise the antennas above the buildings, demanding a tower over {{convert|300|m|ft|0}} tall. Additionally, at the time, most data communications took place over ] links, whose dish antenna covered the roofs of large buildings. As each new skyscraper was added to the downtown, former line-of-sight links were no longer possible. CN intended to rent "hub" space for microwave links, visible from almost any building in the Toronto area. The CN Tower can be seen from at least as far away as Kennedy Street in ], approximately {{convert|40|km|mi|0}} to the north, 60&nbsp;km east of Toronto, in ], and from several points on the south shore of ], {{convert|48|km|mi|0}} to the south in New York state in the United States.{{Or|date=July 2009}}

The original plan for the tower envisioned a tripod consisting of three independent cylindrical "pillars" linked at various heights by structural bridges. Had it been built, this design would have been considerably shorter, with the metal antenna located roughly where the concrete section between the main level and the Sky Pod lies today. As the design effort continued, it evolved into the current design with a single continuous hexagonal core to the Sky Pod, with three support legs blended into the hexagon below the main level, forming a large Y-shape structure at the ground level.

The idea for the main level in its current form evolved around this time, but the Sky Pod was not part of the plans until some time later. One engineer in particular felt that visitors would feel the higher observation deck would be worth paying extra for, and the costs in terms of construction were not prohibitive. It was also some time around this point that it was realized that the tower could become the world's tallest structure, and plans were changed to incorporate subtle modifications throughout the structure to this end.

On June 26, 1986, the ten-year anniversary of the tower's opening, high-rise firefighting and rescue advocate ], in a sponsored publicity event, used his hands and feet to climb the outside of the tower, a feat he performed twice on the same day. Following both ascents, he used multiple rappels to descend to the ground.<ref></ref>

]

===Construction===
]
Construction on the CN Tower began on February 6, 1973 with massive excavations at the tower base for the foundation. By the time the foundation was complete, {{convert|56000|t|ST LT|0|abbr=on|lk=on}} of ] and ] were removed to a depth of {{convert|15|m|ft|1}} in the centre, and a base incorporating {{convert|7000|m3|cuyd|0}} of ] with {{convert|450|t|ST LT|0}} of ] and {{convert|36|t|ST LT|0}} of ] had been built to a thickness of {{convert|6.7|m|ft|1}}. This portion of the construction was fairly rapid, with only four months needed between the start and the foundation being ready for construction on top.

To build the main support pillar, a hydraulically-raised ] was built at the base. This was a fairly impressive engineering feat on its own, consisting of a large metal platform that raised itself on jacks at about {{convert|6|m|ft|1}} per day as the concrete below set. Concrete was poured continuously by a team of 1,532 people until February 22, 1974, during which it had already become the tallest structure in Canada, surpassing the recently built ], which was built using similar methods. In total, the tower contains {{convert|40500|m3|cuyd|0}} of concrete, all of which was mixed on-site in order to ensure batch consistency. Through the pour, the vertical accuracy of the tower was maintained by comparing the slip form's location to massive ]s hanging from it, observed by small telescopes from the ground. Over the height of the tower, it varies from true vertical accuracy by only {{convert|29|mm|in|1}}.

]
]
]
In August 1974, construction of the main level commenced. Using 45 hydraulic jacks attached to cables strung from a temporary steel crown anchored to the top of the tower, twelve giant steel and wooden bracket forms were slowly raised, ultimately taking about a week to crawl up to their final position. These forms were used to create the brackets that support the main level, as well as a base for the construction of the main level itself. The Sky Pod was built of concrete poured into a wooden frame attached to rebar at the lower level deck, and then reinforced with a large steel compression band around the outside.

The antenna was originally to be raised by crane as well, but during construction the ] helicopter became available when the ] sold off theirs to civilian operators. The helicopter, named "Olga", was first used to remove the crane, and then flew the antenna up in 36 sections. The flights of the antenna pieces were a minor tourist attraction of their own, and the schedule was printed in the local newspapers. Use of the helicopter saved months of construction time, with this phase taking only three and a half weeks instead of the planned six months. The tower was topped off on April 2, 1975 after 26 months of construction, officially capturing the height record from Moscow's ], and bringing the total mass to {{convert|118000|t|ST LT|0|lk=on}}.

Two years into the construction, plans for Metro Centre were scrapped, leaving the tower isolated on the Railway Lands in what was then a largely abandoned light-industrial space. This caused serious problems for tourists to access the tower. Ned Baldwin, project architect with John Andrews, wrote at the time that "All of the logic which dictated the design of the lower accommodation has been upset," and that "Under such ludicrous circumstances Canadian National would hardly have chosen this location to build."<ref>Fulford, Robert (1995). ''Accidental city: the transformation of Toronto.'' MacFarlane, Walter & Ross. p. 32.</ref>

===Opening===
The CN Tower opened to the public on June 26, 1976, although the official opening date was October 1. The construction costs of approximately ]63 million ($330 million in 2005) were repaid in fifteen years. ] sold the tower prior to taking the company private in 1995, when they decided to divest themselves of all operations not directly related to their core freight shipping businesses.

As the area around the tower was developed, particularly with the introduction of the ] and ] (known as the SkyDome before 2005), the former Railway Lands were redeveloped and the tower became the centre of a newly developing entertainment area. Access was greatly improved with the construction of the SkyWalk in 1989, which connected the tower and SkyDome to the nearby railway and subway station, ] and, in turn, to the city's ] underground pedestrian system. By the mid-1990s, it was the centre of a thriving tourist district. The entire area continues to be an area of intense building, notably a boom in ] construction in the 2000s and the 2010s.

From 1997 to January 2004, ] 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 north side leg to inside the core of the building, a conversion that also added nine stairs to the climb.

The CN Tower was closed during the ] on June 26–27, 2010, for security reasons, given its proximity to the Metro Toronto Convention Centre.

==Structure==
]
]
The CN Tower consists of several substructures. The main portion of the tower is a hollow concrete hexagonal pillar containing the six ]s, ], and power and plumbing connections. On top of this is a {{convert|102|m|ft|1|adj=on}} tall metal broadcast antenna, carrying TV and radio signals. There are two visitor areas: the main deck level (formerly known as ''SkyPod'') located at {{convert|346|m|ft|0}}, and the higher Sky Pod (formerly known as "Space Deck") at {{convert|446.5|m|ft|0}},<ref>{{cite web |url= http://skyscraperpage.com/cities/?buildingID=21|title= CN Tower|accessdate=2008-04-09|work= SkyscraperPage.com|publisher= Skyscraper Source Media}}</ref> just below the metal ]. The hexagonal shape can be seen between the two areas; however, below the main deck, three large supporting legs give the tower the appearance of a large ].

The main level is seven storeys, some of which are open to the public. Below the public areas&nbsp;— at {{convert|338|m|ft|1}}&nbsp;— is a large white donut-shaped ] containing the structure's microwave receivers. The ] and outdoor observation deck are at {{convert|342|m|ft|1}}. The glass floor has an area of {{convert|24|m2|sqft|0}} and can withstand a pressure of {{convert|4100|kPa|psi|0|lk=on}}. The floor's thermal glass units are {{convert|64|mm|in|1}} thick, consisting of a pane of {{convert|25|mm|in|1|adj=on}} laminated glass, {{convert|25|mm|in|1}} airspace and a pane of {{convert|13|mm|in|1|adj=on}} laminated glass. Some people experience ] when standing on the glass floor and looking down at the ground {{convert|342|m|ft|1}} below. In 2008, one elevator was upgraded to add a glass floor panel, believed to have the highest vertical rise of any elevator equipped with this feature.<ref>{{cite news |author= Canadian Press|authorlink= Canadian Press|coauthors= |title= CN Tower's glass-floor elevator aims for record|url= http://www.thestar.com/News/GTA/article/412944|work= ]|publisher= ]|date= 2008-04-09|accessdate=2008-04-09 }} {{cite news |last= Loriggio|first=Paola|title= CN Tower unveils glass-floor elevator|url= http://www.thestar.com/News/GTA/article/413153|work= ]|publisher= ]|date= 2008-04-10|accessdate=2008-04-09 }} Both linked pages include a video of the elevator with glass floor in operation.</ref> The Horizons Cafe and the lookout level are at {{convert|346|m|ft|1}}. The 360 Restaurant, a ] that completes a full rotation once every 72 minutes, is at {{convert|351|m|ft|1}}. When the tower first opened, it also featured a disco named Sparkles, billed as the highest disco and dance floor in the world.{{Citation needed|date=March 2010}}

The Sky Pod is the second-highest public ] in the world, surpassed only by the ].<ref name=swfc-e>{{Cite web |title=Shanghai World Financial Center |url=http://www.emporis.com/en/wm/bu/?id=shanghaiworldfinancialcenter-shanghai-china |accessdate=2008-05-22 |publisher=Emporis.com}}</ref> On a clear day, it is possible to see 100 to 120 kilometres (62–75&nbsp;mi) away, to the city of ] across ] in the United States, the mist rising from ], or the shores of ].<ref>{{cite web|url=http://www.frommers.com/destinations/toronto/A21082.html|title=CN Tower-Frommer's Review|accessdate=2009-07-22}}</ref>

A metal staircase reaches the main deck level after 1,776 steps,<ref name=CNSTEPS>{{cite news |title= Man climbs CN Tower steps in wheelchair|url= http://www.cbc.ca/canada/story/2002/09/26/wheelchair_020926.html|work= ]|publisher= ]|date= 2002-09-27|accessdate=2008-01-04 }}</ref> and the Sky Pod 100 metres above after 2,579 steps; it is the tallest metal staircase on Earth. These stairs are intended for emergency use only and are not open to the public, except for two times per year for charity stair-climb events.<ref name=WWFClimb>Citing as evidence of one of the climbs, the WWF's 18<sup>th</sup> annual event: {{cite web |url= http://wwfcentral.ca/NetCommunity/Page.aspx?pid=500&srcid=500|title= 18th Annual Canada Life CN Tower Climb for WWF Canada|accessdate=2008-03-20 |publisher= ] Canada}}</ref><ref name=TorontoStarSteps>{{cite news |first= Leslie|last= Ferenc|authorlink= |title= Corporate climbers ready to step up for charity|url= http://www.thestar.com/News/article/266851|work= ]|publisher= ]|location = Toronto|date= 2007-10-15|accessdate=2008-03-20 }}</ref> The average climber takes approximately 30 minutes to climb to the base of the radome, but the fastest climb on record is 7 minutes and 52 seconds in 1989 by Brendan Keenoy, an ] Officer.<ref name=TorontoStarSteps /> In 2002, Canadian ] and ] champion ] climbed the stairs of the tower in a specially designed ]. The stairs were originally on one of the three sides of the tower, with a glass view, but these were later replaced with the third elevator pair and the stairs were moved to the inside of the core.<ref name=CNSTEPS />

==Falling ice danger==
]
A ] storm on March 2, 2007 resulted in a layer of ice several centimetres thick forming on the side of the tower and other downtown buildings. The sun thawed the ice, and winds of up to {{convert|90|km/h|mph|0|abbr=on}} blew some of it away from the structure. There were fears that cars and windows of nearby buildings would be smashed by large chunks of ice. In response, police closed some streets surrounding the tower. During morning rush hour on March 5, police expanded the area of closed streets to include the ] {{convert|310|m|ft|0}} away from the tower, as increased winds blew the ice farther away, as far north as ], {{convert|490|m|ft|0}} away, where a ] window was shattered.

On March 6, the Gardiner Expressway was reopened after winds died down.<ref>{{cite news|url=http://www.citynews.ca/news/features_8415.aspx|title=Video: Falling CN Tower Ice|publisher=] |date=2007-03-02|accessdate=2007-06-26}}</ref> It was the first time such an event had posed a threat to public safety.

==Safety features==
]
In August 2000, a fire broke out at the ] in Moscow. It killed three people and caused extensive damage. The fire was blamed on poor maintenance and outdated equipment. The failure of the fire-suppression systems and the lack of proper equipment for firefighters allowed the fire to destroy most of the interior and spark fears the tower might even collapse.

The Ostankino Tower was completed only nine years before the CN Tower, and is only 13 metres (44&nbsp;ft) shorter.<ref name=doom> by Helen Womackin, The Independent, August 29, 2000.</ref> The parallels between the towers led to some concern that the CN Tower could be at risk of a similar tragedy. However, Canadian officials subsequently stated that it is "highly unlikely" that a similar disaster could occur at the CN Tower as it has important safeguards that were not present in the Ostankino Tower. Specifically, officials cited:

* the fireproof building materials used in the tower's construction,
* frequent and stringent safety inspections,
* an extensive sprinkler system,
* a 24-hour emergency monitoring operation,
* two 68,160-litre (15,000-imperial gallon) water reservoirs at the top, which are automatically replenished,
* a fire hose at the base of the structure capable of sending 2725 litres (600 imperial gallons) a minute to any location in the tower,
* a ban on gas appliances anywhere in the tower (including the restaurant in the main pod),
* an elevator that can be used during a fire as it runs up the outside of the building and can be powered by three emergency generators at the base of the structure (unlike the elevator at the Ostankino tower, which seriously malfunctioned).<ref name=safety>{{cite news|url=http://www.cbc.ca/canada/story/2000/08/28/CN000828.html|date=2000-11-10|title=What if the CN Tower Caught Fire?|work= ]|publisher= ]|accessdate=2007-06-26}}</ref>

Officials also noted that the CN Tower has an excellent safety record and that there has never been an accidental fire in the tower since it was opened in 1976.<ref name=safety /> Moreover, other supertall structures built between 1967–1976&nbsp;– such as the ] (formerly the Sears Tower), the ] (until its ]), the ], the ], the ], and ]&nbsp;– also have excellent safety records, which suggests that the ] accident was a rare safety failure, and that the likelihood of similar events occurring at other supertall structures is extremely low.

==Lighting==
]
The CN Tower was once lit at night with ] lights, but they were removed in 1997 because they were expensive and inefficient to repair. In June 2007, the tower was outfitted with 1,330 super-bright ] lights inside the elevator shafts, shooting up over the "bubble" and upward to the top of the tower's mast to light the tower from dusk until 2 a.m. The official opening ceremony took place on June 28 before the ] holiday weekend. The tower changes its lighting scheme on holidays and to commemorate major events. After the ] in Toronto, the tower was lit up in green and white to represent the colours of the Grey Cup champion ].<ref name="LED">{{cite press release |title= Highlighting the CN Tower&nbsp;— Testing of Innovative Illumination Technology Begins Early June 2007|publisher= CN Tower|date= 2007-05-28|url= http://www.cntower.ca/portal/SmartDefault.aspx?at=1577|accessdate= 2008-04-09 }}</ref>

Programmed from a ] with a ], the LEDs use less energy to light than the previously used incandescent lights (10% less energy than the dimly lit version and 60% less than the brightly lit version). The estimated cost to use the LEDs is $1,000 per month.

During the spring and autumn ] seasons, the lights will be turned off to comply with the voluntary Fatal Light Awareness Program, which "encourages buildings to dim unnecessary exterior lighting to mitigate bird mortality during spring and summer migration."<ref></ref>{{Dead link|date=April 2008}}

==Size comparisons==
], Dubai<br />• CN Tower, Toronto<br />• ], Chicago]]

===Sears Tower/One World Trade Center/Chicago Spire===
The CN Tower is the tallest freestanding structure in the ]. Currently, the only other ] to exceed {{convert|500|m|ft|1|abbr=on}} in height is the ] (formerly known as Sears Tower) in ], which stands at {{convert|527|m|ft|1|abbr=on}} when measured to its pinnacle. ], currently under construction in ], is expected to have a pinnacle height of {{convert|1776|ft|m|1|abbr=on}}, or approximately {{convert|12|m|ft|1|abbr=on}} shorter than the CN Tower. Due to the symbolism of the number 1776 (the year of the signing of the ]), the height of One World Trade Center is unlikely to be increased. The ] was expected to exceed the height of the CN Tower, but its construction has been halted due to financial difficulties and its completion remains uncertain.

===Future structures===
Between 2010 and 2013, the rank of the CN Tower in the list of the world tallest structures is expected to drop considerably. At least seven structures currently under construction, all of which are scheduled to be completed by 2013, are expected to exceed the CN Tower's height of 553.33 metres once completed.

==Controversy over the "world's tallest" title==
]
{{POV-section|date=January 2009}}
] has called the CN Tower "the world's tallest self-supporting tower" and "the world's tallest free-standing tower".<ref name="Guinness 1982">
{{Cite book |last=McWhirter|first=Norris| authorlink= Norris McWhirter| coauthors= | title=Guinness Book of World Records 1982 | year= 1981| publisher=]| location= New York| isbn=978-0-8069-0225-8|oclc=7902975| pages=704}} Reference is on page 275.</ref><ref name="Guinness 2005">{{waybackdate |site= http://www.guinnessworldrecords.com/content_pages/record_subcategory.asp?txtDirection=right&;txtButtonWasHit=true&txtPage=4&subcategoryid=37 |date= 20040925071143| title= Guinness Book of World Records 2005 - Science and Technology << Buildings }}</ref> Although Guinness did list this description of the CN Tower under the heading "tallest building" at least once,<ref name="Guinness 2005"/> it has also listed it under "tallest tower", omitting it from its list of "tallest buildings."<ref name="Guinness 1982"/> In 1996, Guinness changed the tower's classification to "World's Tallest Building and Freestanding Structure". ] and the ] both list the CN Tower as the ], and specifically state that the CN Tower is not a true building, thereby awarding the title of ] to ], which is {{convert|44|m|ft|0}} shorter than the CN Tower.<ref name="info">{{cite web |url= http://www.infoplease.com/ipa/A0886190.html|title= World's Tallest Towers|accessdate=2008-04-10 |work= infoplease|publisher= ]}}</ref><ref name=CTBUH>{{cite web |url= http://www.ctbuh.org/Resources/TallestDatabase/tabid/123/Default.aspx|title= CTBUH Tall Building Database|accessdate=2008-04-10 |date= |work= |publisher= ]}}</ref> The tower's official web site, however, still claims it is the "world's tallest building" as of 2008.<ref name=CNCA>
{{cite web |url= http://www.cntower.ca/portal|title= Home Page|accessdate=2008-04-10 |date= |work= CN Tower official web site|publisher= }}</ref>

Although the CN Tower contains a restaurant, a gift shop, and multiple observation levels, it does not have floors continuously from the ground, and therefore ] by the Council on Tall Buildings and Urban Habitat (CTBUH) or Emporis. CTBUH defines a ] as "a structure that is designed for residential, business, or manufacturing purposes. An essential characteristic of a building is that it has floors."<ref name=CTBUH/> The CN Tower and other similar structures – such as the ] in ], ]; the ] in ], ]; the ] in ]; and the ] in ], ] – are categorized as "towers", which are free-standing structures that may have observation decks and a few other habitable levels, but do not have floors from the ground up. The CN Tower is the tallest tower by this definition.<ref name="info"/>

Taller than the CN Tower are numerous ] which are held in place by ]s, the tallest being the ] in ] at {{convert|628|m|ft|0}} tall, leading to ] between these and "free-standing" structures. Additionally, the ] stands {{convert|610|m|ft|0}} above its base on the bottom of the ], but only the top {{convert|75|m|ft|0}} of this ] are above water, and the structure is thus partially supported by its ]. Like the CN Tower, none of these taller structures are commonly considered buildings.

On September 12, 2007, the ], which is a hotel, residential and commercial building in ], ] and was formerly known as Burj Dubai, passed the CN Tower's 553.33 metre<ref name="CNTower"/> height. The CN Tower held the record of tallest free-standing structure on land for over 30 years.<ref name="CBCSurpassed" /> The tower, as of 2009, stands as the third-tallest free-standing structure on land in the world and the second-tallest free-standing tower, after the ] of the ] in China.

After Burj Khalifa had been formally recognized by the Guinness Book of World Records as the world's tallest freestanding structure, Guinness re-certified CN Tower as the world's tallest freestanding tower.<ref>{{cite web|url=http://www.thestar.com/news/gta/article/698891|title=CN tower now the 'world's tallest freestanding tower'|last=Daubs|first=Katie|date=2009-09-22|publisher=Toronto Star|accessdate=2009-09-22}}</ref> The tower definition used by Guinness was defined by ] as 'a building in which less than 50% of the construction is usable floor space'. Guinness World Records editor-in-chief Craig Glenday announced Burj Khalifa was not classified as tower because it has too much usable floor space to be considered to be a tower.<ref></ref> CN Tower still held world records for highest above ground wine cellar (in 360 Restaurant) at 351 metres, highest above ground restaurant at 346 metres (Horizons Restaurant),<ref></ref> and tallest free-standing concrete tower during Guinness's recertification.

===Other height records===
Since the construction of the tower had been completed, it has gained following world height records<ref></ref>:
{| class="wikitable"
|-
!Record
!Owner
!Value
!Time period
!Succeeded by
|-
|World's highest public observation gallery||Sky Pod||{{convert|447|m|ft}}||?||-
|-
|World's highest bar||Horizons Restaurant||{{convert|346|m|ft}}||2009-09-21&nbsp;– present||-
|-
|World's longest metal staircase||CN Tower||2,579 steps||?||-
|-
|World's highest glass floor||CN Tower||{{convert|342|m|ft}}||2009||Sears Tower, Chicago
|-
|World's highest and largest revolving restaurant||360 Restaurant||{{convert|351|m|ft}}||?||-
|-
|World's highest wine cellar||360 Restaurant||{{convert|351|m|ft}}||?||-
|-
|}

== Use==
]
The CN Tower has been and continues to be used as a communications tower for a number of different media and by numerous companies.

=== Television broadcasters ===
{| class="wikitable"
|-
! Callsign
! Analog Channel
! Digital Channel
! Affiliation
! Branding
|-
| ]
| 5
| 20
| ]
| CBC Television
|-
| ]
| 9
| 40
| ]
| CTV Toronto
|-
| ]
| 19
| 51
| ]
| TVOntario
|-
| ]
| 25
| 24
| ]
| Radio-Canada
|-
| ]
| 41
| 65 (assigned)
| ]
| Global
|-
| ]
| 47
| 64 (from alternate site)
| ]
| OMNI.1
|-
| ]
| 52
| 66
| Independent
| Sun TV
|-
| ]
| 57
| 53
| ]
| Citytv
|-
|}

=== Radio ===

There is no AM broadcasting on the CN Tower.<ref>{{cite web |url= http://www.fcc.gov/fcc-bin/amq?state=ON&call=&arn=&city=Toronto&freq=530&fre2=1700&type=0&facid=&class=&list=1&dist=15&dlat2=43&mlat2=38&slat2=30.67&NS=N&dlon2=79&mlon2=23&slon2=14.27&EW=W&size=9 |title= AM Query & AM List Results|accessdate=2008-04-09 |date= 2008-04-09|work= |publisher= ] - Audio Division}}</ref> The FM antennas are situated {{convert|421|m|ft|0}} above ground.

{| class="wikitable" width="100%" align="center" style="text-align: center"
|-
! Callsign<ref>{{cite web |url= http://www.fcc.gov/fcc-bin/fmq?state=&call=&city=&arn=&serv=&vac=&freq=0.0&fre2=107.9&facid=&class=&dkt=&list=1&dist=10&dlat2=43&mlat2=38&slat2=30.67&NS=N&dlon2=79&mlon2=23&slon2=14.27&EW=W&size=9 |title= FM Query & FM List Results|accessdate=2008-04-09 |date= 2008-04-09|work= |publisher= ] - Audio Division}}</ref> !! Frequency !! ERP !! Branding !! Notes
|-
| colspan="4"|Master FM || align="left"|Consortium of Toronto broadcasters for ]
|-
| ] || 91.1&nbsp;MHz || 40&nbsp;kW || JAZZ.FM91 ||
|-
| ] || 94.1&nbsp;MHz || 38&nbsp;kW || ] ||
|-
| ] || 96.3&nbsp;MHz || 38&nbsp;kW || Classical 96 ||
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| ] || 97.3&nbsp;MHz || 4&nbsp;kW || boom 97.3 ||
|-
| ] || 98.1&nbsp;MHz || 44&nbsp;kW || 98.1 CHFI ||
|-
| ] || 99.9&nbsp;MHz || 40&nbsp;kW || Virgin Radio 99.9FM||
|-
| ] || 100.7&nbsp;MHz || 4&nbsp;kW || CHIN Radio || align= "left"|Primarily in Italian and Portuguese
|-
| ] || 102.1&nbsp;MHz || 35&nbsp;kW actual (100&nbsp;kW ]) || 102.1 the Edge
|-
| ] || 104.5&nbsp;MHz || 40&nbsp;kW || 104.5 CHUM FM ||
|-
| ] || 107.1&nbsp;MHz || 40&nbsp;kW || Classic Rock Q 107 ||
|}

=== Cellular and paging providers ===
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=== Communications ===
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* ] ]s "2-Tango" (]) and "4-Tango" (440/70&nbsp;cm ])&nbsp;– owned and operated by the Toronto FM Communications Society, under callsign VE3TWR<ref name="ARES">
{{cite web |url=http://ares.meskes.ca/frequencies.html |title=Toronto ARES Channels |accessdate=2006-08-03 |date=2005-10-26 }}</ref>

== Media placement ==
] stadium]]
{{Trivia|date=February 2009}}
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***''Unlimited'' expansion pack
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* '']''<ref>{{cite web|url=http://www.thestar.com/News/GTA/article/468922|title=Toronto a hot spot for Mexican tourists|last=Doolittle|first=Robyn|date=2008-07-29|publisher=Toronto Star|accessdate=2008-07-29}}</ref>

== See also ==
{{Portal|Toronto}}
{{Commons category}}
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==References==
{{Reflist|2}}

==External links==
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{{Succession box|title=World's tallest free-standing structure <br/><small>553.33 m (1,815 ft 5 in)</small>|before=]|after=]|years= 1976-2007}}
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Revision as of 16:00, 14 October 2010

wats up everybody