CN Tower

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CN Tower
Image of the object
CN Tower 2012 from Bremner Blvd
Basic data
Place: Toronto - Old Toronto
Province: Ontario
Country: Canada
Altitude : 81  m
Coordinates: 43 ° 38 ′ 33.3 "  N , 79 ° 23 ′ 13.5"  W.
Use: TV tower , telecommunications tower , radio transmitter , revolving restaurant , observation tower
Accessibility: TV tower open to the public
Owner : Canada Lands Company
Tower data
Construction time : 1973-1976
Construction costs : C $ 63 million
Client : Canadian National Railway,
CN Tower Ltd.
Architect : John Andrews in collaboration with WZMH Architects
Building materials : Concrete , steel , reinforced concrete , glass
Operating time: since 1976
Total height : 553.33  m
Viewing platforms: 342  m , 446.5 m
Restaurants: 346  m , 351 m
Operating rooms: 338  m , 355 m, 359 m, 362 m
Total mass : 117,910  t
Data on the transmission system
Waveband : FM transmitter
Broadcasting : VHF broadcasting
Send types: NTSC , DVB-T , cellular radio , directional radio , amateur radio service
Further data
named after: Canadian National Railway
Groundbreaking : February 6, 1973
Completion: February 6, 1976
Commissioning the transmitter system: May 1, 1976
Opening of the viewing platform: June 26, 1976
Official opening: October 1, 1976

Position map
CN Tower (Ontario)
CN Tower (43 ° 38 ′ 33.32 ″ N, 79 ° 23 ′ 13.51 ″ W)
CN Tower
Localization of Ontario in Canada

The CN Tower [ siːˈɛn ˌtʰaʊ̯ɚ ] ( Canadian National Tower , French La Tour CN ) in the south of downtown Toronto is a 553 meter high television tower and landmark of the city. From 1975 to 2009 it was the tallest television tower in the world. At the same time, from 1975 to 2007, when the Burj Khalifa reached a height of 555.30 meters, it was the highest free-standing and non-guyed structure on earth. It is used for telecommunications and the distribution of over 30 television and radio programs.

The construction time of the television tower was only 40 months, which, especially for the conditions at the time, represented an unusual construction achievement. The tower was built to improve radio transmission and was originally not intended to be open to the public. Today it is the main tourist attraction of the Canadian metropolis and records up to two million visitors annually with its various levels, viewing platforms and the revolving restaurant .

The tower, which is architecturally regarded as successful in the professional world, has developed over the years into a symbol of national importance for Canada and was included in the list of the Seven Wonders of the Modern World by the American Society of Civil Engineers in 1995. Since its completion, it has often been the setting for spectacular stunts and record performances.

Location and surroundings

Location of the CN Tower in Downtown Toronto

The CN Tower is located near Lake Ontario in the immediate vicinity of the Rogers Center, just outside the city center dominated by high-rise buildings, between the railway lines and the Gardiner Expressway . With Union Station , Toronto's main train station , which is also adjacent , the tower is connected to the underground pedestrian system PATH via a skywalk . Opposite the television tower is the John Street Roundhouse , a ring locomotive shed built in 1897 and reconstructed in 1995 , which houses historic locomotives and a brewery.

The multi-purpose hall Scotiabank Arena is around 800 meters east of the tower ; 200 meters north, on the other side of the train tracks, is the Metro Toronto Convention Center . These structures, including the CN Tower, were created as part of the urban redesign of the former station site.

The space between the tower and the neighboring Rogers Center was named Bobbie Rosenfeld Park in 1991 in memory of the athlete Bobbie Rosenfeld . The square, which is laid out with cobblestones, is planted with numerous plants. At the southern end of Bremner Avenue, not far from the CN Tower, there is a fountain artwork called Salmon Run , which was created by the artist Susan Schelle and depicts salmon jumping up. The fountain was restored in 2006 and its function restored.



The logo of the Canadian National Railway was also the logo of the CN Tower until 1995

The acronym CN is originally derived from C anadian N ational Railways from, the Canadian Railway Company, the tower together with the Canadian Broadcasting Corporation to improve television reception through its subsidiary (CBC) CN Tower Limited was built. In 1995 the railroad company sold the television tower to the state real estate company Canada Lands Company . Until then, the tower had the lettering CN, which was identical to the logo of the railway company. This lettering was no longer used after the sale.

In particular because of the objection of locals, the name CN Tower was retained. After the split from Canadian National Railway, the name of the tower was to be abbreviated from Canada's National Tower or later Canadian National Tower . The common name, however, remained the abbreviation CN Tower used in English, with which the city and the tower also advertise. Since French is the second official language of Canada, the tower is referred to on signs and publications in addition to English with the French abbreviation La Tour CN , or Tour nationale du Canada .


The idea for a transmission tower to distribute radio and television programs in Toronto goes back to the 1960s. During this time, the skyscrapers in the Financial District (→ List of the tallest buildings in Toronto ) grew and worsened the reception of radio and television stations. The density and height of the new high-rise buildings weakened the signals from the Toronto television stations, in some cases considerably, which was usually noticeable through the overlapping of two programs. Radio reception was also weakened.

The first proposals were made in 1968; Initially, the tower was supposed to be a transmission mast with a height of at least 350 meters with no public area. In the course of the planning phase, economic considerations demanded that the transmission coverage also had to be guaranteed for the Toronto area, so that the tower was again planned significantly higher. In 1970 the final decision on the construction was made, and tests in the wind tunnel began a year later . Since the location had already been determined, the client had geologists from the University of Toronto examine the building site. Boreholes up to 91 meters deep showed that the tower, which was then estimated to be 457 meters high and founded on rock at a depth of 15.2 meters, would have sufficient stability.

The company NCK Engineering Limited placed the senior structural engineer. Structural engineers were RR Nicolet (NCK) and Franz Kroll. The architect of the CN Tower was John Andrews in collaboration with The Webb, Zerafa, Menkes, Housden Partnership (today: WZMH Architects ). Andrews' original idea was more functional in nature and less aimed at creating a particularly defining design for the city. In 1972 the final shape of the tower was chosen from various designs and it was decided to open the tower to the public. The curved tower shaft corresponds to the original idea, which envisaged three masts connected by a bridge structure. However, this construction would have been significantly lower and would not have met the requirements for radio transmission. Therefore, the client decided on a single hexagonal core supported by three foot structures. This construction, which tapers upwards, has a Y-shaped cross-section.

The construction of the television tower was part of a large-scale redesign of the so-called CityPlace , a district that was characterized by a large marshalling yard . This became superfluous after the creation of new transshipment points for the railroad outside the city center.


Foundation work on the CN Tower in 1973

The groundbreaking ceremony took place on February 6, 1973. The construction costs amounted to 63 million Canadian dollars , which corresponds to about 300 million dollars in 2009 due to inflation. The 1998 renovation and expansion cost $ 26 million.

A total of 56,000 tons of slate were dug to a depth of around 15 meters for the foundation . The foundation consists of 7000 cubic meters of concrete and was reinforced with 450 tons of reinforcing steel . In addition, 36 tons of prestressing steel were used. The foundation work was completed in around four months.

The post, made of pre-stressed concrete, was poured with the help of a sliding formwork . The built-in tendons are up to 454 meters long. Special measures had to be taken for the vertical erection of the tower. To do this, a steel cylinder weighing more than 100 kilograms was suspended from a wire rope in the hexagonal hollow core of the shaft. In order to maintain the vertical, measurements were taken every two hours with optical instruments. The 553 meter high tower deviates only 27 millimeters from the vertical. With this special procedure from Sweden, the tower grew gradually by up to 6 meters per day. In order to check the compressive strength of the concrete, quick tests had to be carried out, as the normalized strength of the concrete is only determined after 28 days. Work on the tower shaft lasted until February 22, 1974. At that time, the construction towered over the tallest structure in Canada, the 380-meter-high Inco Superstack chimney in Greater Sudbury . A special concrete mix with a water-cement ratio of 0.42 was used to build the CN Tower. Steel elements with a diameter of 35 millimeters were used for the reinforcement , which means that the resistance to corrosion extends for 500 years.

CN Tower nearing completion

According to the original planning, the CN Tower should have had a total height of around 522.5 meters. During this construction phase, the client saw the chance that the tower could become the tallest structure on earth by raising it. The design team suggested this option to lead engineer Norman McMillan. After a detailed examination, the client decided, contrary to the original plan, to raise the shaft of the structure between the planned tower cage and the platform above by 30.5 meters.

At the foot of the CN Tower, work began on the seven-story tower cage in August 1974 . 45 hydraulic lifting devices were required to lift the 318-tonne structure to a height of 350.5 meters . Clamping devices ensured that the tower cage could not slip off. To build the upper levels, shotcrete was poured into twelve prefabricated wooden frames that were held together with steel clips. The shell construction on the tower cage lasted until late autumn 1975.

After the completion of the tower top, the construction of the upper observation deck began Sky Pod the cantilever . To prevent the boom from collapsing, a directional beam was used to monitor the tower base wall. Above the Sky Pod, a concrete shaft around 4.80 meters high formed the basis for the antenna.

March 1975: the Sikorsky S-64E heaves a transmitter mast element from the ground

The transmission tower made of steel has been assembled from individual parts and 44 with a transport helicopter of the type Sikorsky S-64 promoted E named Olga on the tip of the Sky Pod. This reduced the antenna construction time to three and a half weeks. With conventional methods it would have taken half a year. The heaviest section weighed 7.26 tons; the last one was installed on April 2, 1975. The painting work on the antenna mast was carried out by four workers in eleven days. On the roof edge of the Sky Pod, heating wires were laid in some places to prevent icing and the risk of falling chunks of ice. In other places, the surface was covered with smooth, five centimeters thick, fiberglass-reinforced plastic to make it difficult for ice to set. In total, during the forty month construction period at the CN Tower, 1,537 workers worked in multiple shifts, 24 hours a day, five days a week. On November 9, 1975, there was a scandal when Bill Eustace became the first person to jump from the tower with a parachute. Since he was part of the construction team, he was dismissed without notice.

After a construction period of over three years, the CN Tower was completed on February 6, 1976 and replaced the Ostankino television tower in Moscow with 540 meters as the tallest free-standing structure in the world.

Since opening

The CN Tower logo used since 1995

The tower was open to the public for the first time on June 26, 1976 from midnight; On that day, over 12,000 people visited the building. The official opening took place on October 1, 1976 in the presence of the then Prime Minister Pierre Trudeau . The television tower was initially very isolated on the property of the railway company. The plans for the Metro Center were discarded, so that access for tourists was initially problematic. The architect Ned Baldwin involved in the project criticized the location at the time:

"All of the logic which dictated the design of the lower accommodation has been upset, [...] Under such ludicrous circumstances Canadian National would hardly have chosen this location to build."

"The entire logic that was given for the design of the lower quarter has been reversed, [...] Under such ridiculous circumstances the Canadian National would hardly have chosen this place for construction."

Over the years, the barren area around the CN Tower has been made more attractive through the construction of sports facilities and apartment buildings and integrated into Toronto's urban planning concept.

On 26 June 1986, climbed free climber Dan Goodwin, who had been committed to the tenth anniversary, twice without additional tools on the elevator shaft of the tower up and then rappelled off again. In the course of its existence, the tower has repeatedly been the scene of stunts during filming (→  media ) and record performances (→  records ). In 1995 the American Society of Civil Engineers selected the CN Tower as the Architectural Wonder of the World . In March 1997 two new elevators were installed, which increased the transport capacity. To do this, part of the stairwell had to be rebuilt.

View through the glass floor opened in 1994
CN Tower as part of the Toronto skyline (August 2016)

Since its opening, the tower has been regularly renewed and expanded with new attractions. For example, a 23.8 m² glass floor was opened on June 26, 1994, the revolving restaurant was officially reopened on April 25, 1995 after extensive renovation and redesign work, and since May 13, 1997 a wine cellar in the tower basket has been added to the gastronomic offer. After nine months of construction, an arcade area was opened in the tower base on June 26, 1998. In October 2002 the Teflon-coated ring element on the tower cage was replaced; the directional radio transmitters behind it were renewed.

Greenpeace activists climbed on 16 June 2001 on the tower and fastened just below the tower top, a banner with the words "Canada and Bush: Climate Killers." ( "Canada and Bush : climate killer."), Making thus the refusal of Canada to Kyoto climate protocol attentive.

On March 2, 2007, freezing rain caused a layer of ice several centimeters thick on the tower shaft of the CN Tower. A thaw and strong winds of up to 90 km / h loosened the frozen layer of ice from the tower piece by piece, which severely damaged parts of buildings and cars. As a result, on the morning of March 5, the police had to block roads for a day within a radius of almost 500 meters, including the busy Gardiner Expressway .

The CN Tower lost the title of tallest television tower in the world on May 5, 2009 to the Canton Tower in the People's Republic of China . It is currently the third tallest television tower in the world after the Canton Tower and the Tokyo Skytree .


Architecture and construction technology

Sky Pod observation deck
Tower cage

The television tower stands on a Y-shaped prestressed concrete foundation slab corresponding to the tower floor plan . This has three 33.3 meter long arms up to 5.5 meters thick and 18.9 meters wide and is founded on rock at a depth of 15.2 meters. Below the ribs of the tower shaft in the foundation plate there are cavities that were used to tension the 48 tendons of the tower. The tendons vary in length between 144 and 457 meters and each have a tension force of 1.8 meganewtons . 56,000 tons of earth and slate were excavated to build the foundation, the total weight of the tower is 117,910 tons.

Unlike most television towers , the tower shaft consists of a hexagonal tube. Such tower shafts are rarely found in television towers; The St. Chrischona television tower in Switzerland , for example, has a comparable construction . The shaft is supported by three box-shaped "ribs" running on the outside, which suggest a three-legged support structure. These ribs extend over a length of 33.3 meters, have an octagonal cross-section, are 18.9 meters wide and 5.5 meters thick. On the outside, this thickness gradually decreases to 1.2 meters on the top and bottom. The length of the ribs also decreases continuously from 22.7 meters at the base of the tower to the height of the lower tower cage. The external elevators and a stairwell are located between the vertical inner walls of the ribs ; the outer walls are inclined. Due to the extreme height of the structure, there are flight safety lights not only on the antenna mast, but also on the shaft at five different heights at intervals of 70 meters. Lights on the sky pod and above the tower cage also warn.

Floor plan of the CN Tower at the base

The disadvantage of this unusual construction is a large wind resistance area. The wind load is three to four times greater than with a round shaft. Nevertheless, the television tower can withstand gusts of wind up to over 400 km / h. The antenna tip moves only 1.07 meters from vertical in winds of 120 mph (193 km / h). In these wind conditions, the Sky Pod moves 0.46 meters and the tower cage 0.23 meters from the rest position. One advantage of the star-shaped floor plan is that when the tower was built, the formwork only had to be changed on the narrow front sides of the walls with the tower height. In the case of an annular cross-section, however, this must be adapted over the entire circumference. Architecturally, the curved lines strengthen the perception of striving upwards.

The tower cage (main pod) measures 43 meters in diameter and a maximum of 36.5 meters in height and is profiled several times. Its lower part is a 7.50 meter wide, bead-like, Teflon-coated ring made of fiberglass-reinforced plastic, behind which there are directional radio antennas. The upper part of the seven-storey basket, which is clad with stainless steel , reflects the sunshine when the light falls. For aesthetic reasons, a striking red ring can be seen in the upper part of the building. A mobile maintenance cage is permanently attached to the outside of the tower cage, which is parked in a north-westerly direction when not in use. The stairwell and the two elevator shafts extend over the tower cage. The upper end of the three shafts is clad with a silver-colored corrugated stainless steel surface; The machine rooms of the elevator system are located in two shafts.

The tower cage is divided into the following floors:

Schematic model of the tower cage
height function
362 m Operating floor for mechanical equipment
359 m Operating floor with radio equipment for radio transmission
355 m Company floor with radio equipment for TV transmission
351 m Revolving restaurant
346 m Cafe and indoor deck
342 m Glass floor and open air platform
338 m Antenna platform for directional radio antennas

Above the main tower cage, at a height of 446.5 meters, there is another observation platform (sky pod) in the form of a crow's nest , accessible via a separate elevator . The CN Tower is made of prestressed concrete up to a height of 442 meters. Above this is the two-storey Sky Pod. On the upper floor there is a smaller viewing platform with outward sloping windows, so that an almost vertical view down is possible. On the lower floor there is the entrance to the elevator system with small portholes , which can hardly be seen from the outside. Above the Sky Pod, a 102 meter high steel mast acts as an antenna, which is encased in glass fiber reinforced white plastic segments. Various telecommunications equipment and the transmitters for radio and television programs are housed in the mast. The mast tapers towards the top in five steps, each step being marked with a gray, black and red ring for reasons of flight safety. The last part of the mast is red.

Facilities for the public

Visitors on the open-air platform
View from the Sky Pod to the tower cage

Four of the six elevator cabins on the east and west outer walls reach speeds of up to 6 meters per second. A pendulum apparatus registers fluctuations z. B. are wind-related and ensures a reduction in speed if necessary. At top speed, the elevator car operated by the staff gets from the ground floor to the first viewing platform in 58 seconds. The capacity of the Otis elevators is designed to transport up to 1200 visitors per hour. A glass wall provides a view of the outside while driving.

At a height of 342 meters, the tower houses an open observation deck ( Outdoor Observation Deck ) secured by grids, as well as a glazed floor on the lowest floor of the tower cage ( Glass Floor ), and a café (Horizons Café) with 150 seats at 346 meters and a closed viewing platform ( Look Out Level ). The revolving restaurant 360 at a height of 351 meters rotates once every 72 minutes on its own axis. The restaurant, which opened on April 25, 1995, has a capacity of up to 400 guests. On May 13, 1997, the restaurant was expanded to include an extensive wine collection. Up to 9000 bottles are stored in a room at 13 ° C with 65% humidity. All these facilities belong to the seven-story tower cage (English Main Pod ). As an alternative to the elevators, stairs with 2579 steps that are not accessible to visitors lead up to the tower cage. An exception is the main staircase with 1776 steps, on which a running event has been held twice a year since 1977, the proceeds of which are donated to charity.


The EdgeWalk was opened on August 1st, 2011 on the ledge above the revolving restaurant in the tower cage . At a distance of 356 meters, visitors can walk around the tower on a 1.50 meter wide walkway. Because there is no handrail installed here, the people are secured with a climbing harness that is hooked onto a wire rope on a rail above their heads and walks with them as they go around. According to the operator, the EdgeWalk is the world's highest free-hand panoramic walk of its kind.

A special attraction is the 23 m² glass floor in the Glass Floor Deck , which opened on June 26, 1994 . The entire free-standing floor of the lower observation deck consists of 6.35 centimeter thick bulletproof glass plates that can support 38 tons. The individual glass plates measure 1 meter × 1.5 meters and are covered with another 2.5 cm thick layer of tempered glass for insulation. A special replaceable film protects the glass from scratches and wear. Since many visitors did not dare to use this "floor covering", a large part was covered with carpeting. The glass bottom can still be seen from below.

The Sky Pod (447 meters), formerly known as the Space Deck , can only be reached from the tower cage via separate elevators. When the weather is clear, you can see up to 120 kilometers from the Sky Pod, and when the weather is right you can even see the spray of Niagara Falls . (→ 360-degree view of Toronto from the Sky Pod )

On the ground floor of the tower there is an interactive multimedia center, a souvenir shop, a café (Far Coast Café) , an exhibition and a small cinema showing films about the construction of the CN Tower. The cinema hall can alternatively be used as an event room with up to 144 seats. Other rooms in the television tower can also be rented for celebrations or other events. Around 300 events take place there every year. At the foot of the tower there is a small herb garden, the produce of which is processed in the kitchen of the tower restaurant. The CN Tower is regularly looked after by 400 and in the high season by up to 550 employees. It is open all year round except December 25th.


CN Tower illuminated

The CN Tower is illuminated in the evening and at night. The conventional lighting with incandescent lamps was replaced in 2007 by the much cheaper and less maintenance light - emitting diodes . The costs for the lighting amount to around 1000 CAD per month, which corresponds to a saving of over 60% compared to the previous costs.

The lighting was further improved on June 28, 2007. After a three-month installation phase, the tower has been illuminated with 1330 bright light-emitting diodes since then. These illuminate the elevator shafts, the tower cage and the antenna either statically or animated from the inside of the tower until 2:00 a.m. The LED lighting units can be controlled individually and wirelessly by a computer, which means great flexibility in use. The lighting scheme and colors vary depending on the season and the occasion. For example, on its anniversary on June 26th and on Canada Day , the tower always shines in red and white and on Pride Toronto Weekend in June in rainbow colors . On the first day of winter, December 21st, it is illuminated in blue and white. A special light show takes place on New Year's Eve. During the bird migration season from September 22nd to October 30th, the special lighting remains switched off and the tower is only dimmed so that migratory birds are not irritated. For the birth of the prince's son George of Cambridge on July 22, 2013, the tower was illuminated with royal blue.

Safety devices

The tower has active and passive safety and fire fighting equipment. In addition to video surveillance , the tower has a large-area sprinkler system that is connected to two tanks with 68,250 liters of water each. The tank on the upper floor of the tower cage refills automatically when necessary. A fire extinguishing line at the base of the tower can transport up to 2730 liters per minute to any point in the tower. As a passive measure, in addition to a general smoking ban, gas-powered household appliances were banned inside the tower. The flexibility and stability of the structure is designed for earthquakes with a maximum strength of 8.5 on the Richter scale . To protect against lightning strikes, several copper wires are integrated into the foundation as lightning conductors .

National and technical relevance and use

Symbolic character

Romanian postage stamp with the CN Tower as a motif

The considerable height of the CN Tower was already a sign of Canada's efficiency. Its 1815 feet , converted into the Anglo-American system of measurement, indicate a special date in the city's history. In December 1814, British and American diplomats officially ended the British-American War in Ghent, Belgium , during which the city as Fort York was conquered and looted twice.

Not least because of the ubiquity of the CN Tower in the Toronto cityscape, it achieved a cult status similar to that of the Berlin TV tower . The high recognition value has made it a landmark far beyond the city limits and has made the tower a national symbol of all of Canada. The building, which was initially controversial, embodies the upswing in the city that overtook Montreal as the country's largest city in the 1970s . This also means that the tower can be used as a logo or silhouette by companies or institutions.

The CN Tower was a motif on coins and stamps on several occasions. In 1984, for the 150th anniversary of the city of Toronto, a silver dollar coin appeared on which the skyline, the CN Tower and an Indian canoeed. To mark the 30th anniversary of the television tower, a $ 20 silver coin was released in 2006 as part of a series of architectural treasures with a mintage of only 15,000 pieces, which shows the tower in a special photo hologram technique. For the International Postage Stamp Exhibition Capex , the Romanian Post issued a pad edition showing the tower and surrounding buildings. At the turn of the millennium, the Canadian Post paid tribute to the CN Tower on a 46-cent stamp ( Michel no. 1823 or Scott catalog # 1831) with a stamp set with 68 stamps on September 15, 1999, and a stamp with the same motif appeared on March 17th 2000 as a stamp pad (Michel pad number 49). In addition to the tower cage, it shows the cross-section of the tower base and the glass floor.


Toronto is the film capital of Canada; their cityscape is often used as a backdrop for feature films. The skyline dominated by the CN Tower is, for example, in the international films The Sentinel - Whom Can You Trust? and Resident Evil: Apocalypse . Although Police Academy 3 is an American film, part of it was shot in Toronto. The film is set to take place in a major US city; However, one recognizes the skyline of Toronto and the striking tower several times.

In the 1982 action comedy Am Highpoint, the crowd freaks out , the tower is a central location for the film. In the showdown , the film's villain jumps from the roof of the tower cage. In this scene Christopher Plummer was doubled by Dar Robinson , who jumped from the tower secured on a cable. The stunt for the film was shot back in 1980. Stuntman Robinson later repeated the jump for a TV show when he jumped from the tower with a hidden parachute.

Scientific use

Lightning strike in the CN Tower

Very high structures are preferred for geophysical observations and analyzes in thunderstorm research. The CN Tower has served several research institutes since 1978, including the Smithsonian Astrophysical Observatory , for statistical surveys on the spread of magnetic fields in the event of multiple discharges caused by lightning . Because of its extreme height and grounding , the structure attracts lightning and is struck by lightning an average of 75 times a year. For this purpose, several magnetic coils are attached as a measuring device at various points on the antenna mast. A recording device at an altitude of 403 meters stores this data. Measurements in the 1990s showed that the electromagnetic waves created by the lightning strikes can be measured up to a range of two kilometers around the tower. The tower acts like an almost lossless ladder .

Time capsule

In a wall below the observation deck of the CN Tower was an opening on October 1, 1976 time capsule (ger .: time capsule ) included. This capsule contains a sealed letter from former Canadian Prime Minister Pierre Trudeau , a congratulatory letter from then Prime Minister of Ontario Bill Davis , letters from school children, copies of the three daily newspapers Toronto Star , Toronto Sun and The Globe and Mail , notes and coins of various denominations of Canadian money as well as a video about the construction of the tower. It is planned to open the capsule exactly 100 years after the tower was officially inaugurated on October 1, 2076.


Size comparison of high television towers
Skyscraper in Downtown Toronto with CN Tower, looking towards Lake Ontario

Since March 31, 1975, the CN Tower was the tallest non-guyed structure in the world, overtaking the Ostankino television tower in Moscow . The tower took this title according to the definitions of the Guinness Book of Records , the building information database of Emporis and the Council on Tall Buildings and Urban Habitat . According to this, transmission masts such as the 629 meter high KVLY mast or drilling platforms are not used for comparison. For skyscrapers , the structural height is measured from the level of the main entrance to the highest architectural element. Antennas mounted on skyscrapers, such as the Willis Tower in Chicago , are not taken into account. Since a television tower is not recognized as a building for such comparison purposes, but only as a (free-standing) structure, antenna heights are taken into account (the antenna heights are also evaluated for skyscrapers in the term building). If you add the antennas in skyscrapers, there was no high-rise building taller than the CN Tower until 2007. Only after 30 years, on September 11, 2007, with the construction of the Burj Khalifa , the final height of which is 828 meters, did the CN Tower lose the rank of the tallest structure on earth - without counting transmission masts, like the KVLY mast in the USA with 629 meters. Until the topping-out ceremony of the Canton Tower at 600 meters (initially 610 meters, was reduced to 600 meters in 2010) in the People's Republic of China on May 5, 2009, however, it was still the highest television tower. As before, it remains the tallest non-guyed structure on the American double continent.

The (no longer current) reference to the highest observation deck in the world

With the Sky Pod at a height of 447 meters, the CN Tower also held the record for the highest observation deck in the world. Since a publicly accessible platform at 474 meters was opened in the Shanghai World Financial Center in 2008 , this title has also been lost. According to the Guinness Book, the tower still holds the title of the highest wine cellar, which is located at 351 meters together with the revolving restaurant. The metal staircase inside the shaft, designed as an escape route, is the longest in the world within a building with 2579 steps.

The tower's records repeatedly spurred people on to record achievements, some of which were daring jumping and climbing activities, and some of which were sporting "fun records".

  • In 1979 a piano was carried over the stairwell to the viewing platform in 7.5 hours.
  • In 1980 Donn Reynolds set a record for continuous yodelling . He yodelled from the roof of the tower cage for 7 hours and 29 minutes.
  • In 1981, Robert Jezequel set a record for climbing stairs within a day. He climbed the tower a total of 17 times using the stairwell.
  • In 1984 the stuntman Roger Brown plunged down the 1,760 steps between the tower cage and the tower base in 1 hour 51 minutes.
  • In 1999, Ashrita Furman set a record for climbing stairs with a jumping stick . He hopped a total of 1,899 steps up the stairwell in 57 minutes and 15 seconds.
  • In 2002, the Paralympic athlete Jeff Adams climbed the 1,776 steps of the staircase with a wheelchair.
  • From August 17th to 22nd, 2007, the tallest Lego tower in the world was erected in front of the CN Tower at 29.03 meters .

Frequencies and Programs

Tower cage and antenna

With its facilities for communication transmission, the CN Tower serves a variety of different media and operators. The tower sent the first signals before the official opening, on May 1, 1976. These were the two television stations CFTO-TV and CBC-TV. The transmitters for TV programs are located in the upper part of the steel antenna.

Broadcasting from television channels

Abbreviation Analog channel Digital channel Affiliation Brand name
CBLT 5 20th CBC CBC Television
CFTO TV 9 40 CTV CTV Toronto
CICA 19th 51 TVOntario TVOntario
CBLFT 25th 24 Radio Canada Radio Canada
CIII TV 41 65 Global Television Network Global
CFMT TV 47 64 Rogers Communications Omni.1
CKXT TV 52 66 Independent Sun TV
CITY TV 57 53 Citytv Citytv

Broadcasting radio programs

The CN Tower does not emit amplitude-modulated radio programs (AM), only frequency-modulated (FM) programs . The transmitters are located at a height of 421 meters between the tower cage and the sky pod.

Abbreviation frequency ERP Brand name comment
Master FM Merger of broadcasting companies in Toronto for digital audio broadcasting (DAB)
CJRT 091.1 MHz 40 kW JAZZ.FM91
CJAQ 092.5 MHz 40 kW 92.5 Jack FM
CBL 094.1 MHz 38 kW CBC radio 2
CFMZ 096.3 MHz 38 kW Classical 96
CHBM 097.3 MHz 28 kW Boom 97.3
CHFI 098.1 MHz 44 kW 98.1 CHFI
CFMX 099.9 MHz 40 kW 99.9 Mix FM
CHIN 100.7 MHz 4 kW CHIN radio Mainly in Italian and Portuguese
CFNY 102.1 MHz 35 kW currently (100 kW ERP ) 102.1 the Edge
CHUM 104.5 MHz 40 kW CHUM-FM
CILQ 107.1 MHz 40 kW Classic Rock Q 107
Aerial view of downtown Toronto with CN Tower

Mobile operator services



Reference books

  • Meg Greene: The CN Tower , Blackbirch Press, San Diego, CA 2004, ISBN 978-1-4103-0141-3 (English).
  • Peter Marti, Orlando Monsch, Birgit Schilling, Emil Honegger; Society for Civil Engineering (Ed.) Engineering concrete construction . [Background, reinforced concrete, concrete structures; Catalog for a traveling exhibition, which was shown for the first time in 2003 at the ETH Hönggerberg], Vdf Hochschulverlag , Zurich / Singen 2005, ISBN 978-3-7281-2999-4 , pp. 194–196.
  • Franz Knoll: Structural Design Concepts for the Canadian National Tower, Toronto, Canada , Canadian Journal of Civil Engineering, Vol. 2. No. 2, 1975, pp. 123-137 (English).
  • Erwin Heinle , Fritz Leonhardt : Towers of all times - of all cultures . dva , Stuttgart 1997, ISBN 3-421-02931-8 , pp. 246-247.
  • Friedrich von Borries , Matthias Böttger, Florian Heilmeyer: TV-Towers - Fernsehtürme, 8,559 Meters Politics and Architecture - 8,559 Meters Politics and Architecture , Jovis, Berlin 2009, ISBN 978-3-86859-024-1 , pp. 120–125 ( German and English).
  • ERA Architects: Concrete Toronto , University of Chicago Press, Chicago 2007, ISBN 978-1-55245-193-9 , pp. 204-209 (English).

Technical article

  • John A. Bickley, Shondeep Sarkar, Marcel Langlois: CN Tower , in Concrete International , American Concrete Institute 1992, Vol. 14, No. 8, pages 51-55.
  • John A. Bickley: Concrete Technology Aspects of CN Tower , in Journal of the Construction Division , Issue 101, No. 1, ASCE , March 1975, pp. 201-212.
  • Bruno Thürlimann : Foundation structure of the CN Tower (Toronto) in: IABSE congress report, 10/1976, pp. 257-262. ( here online )
  • Frank Knoll: Structural Design Concepts for the Canadian National Tower, Toronto, Canada in: Canadian Journal of Civil Engineering, Vol. 2, No. 2, 1975, pp. 123-137.
  • Alan Davenport, Jaak Monbaliu, Nick Isyumov: CN Tower, Toronto: model and full scale response to wind in: IABSE congress report , 12/1984, pp. 737-746. ( here online )


Web links

Commons : CN Tower  - collection of images, videos and audio files
Video contributions

Individual evidence

  1. Article about the Burj Khalifa ( Memento from September 21, 2007 in the Internet Archive )
  2. a b c Erwin Heinle, Fritz Leonhardt: Towers of all times, of all cultures , p. 246
  3. Public art and monuments ,, accessed on April 27, 2012
  4. ^ Greene: The CN Tower , p. 9
  5. ^ Von Borries, Böttger, Heilmeyer: TV-Towers - Fernsehtürme , page 123
  6. ^ Greene: The CN Tower , p.15
  7. CN Tower at 40: A look back at the design, engineering & construction of Canada's National Tower , Cole Engineering 2016
  8. ^ Greene: The CN Tower , pp. 11/12
  9. Facts and history about the CN Tower (PDF file; 629 kB)
  10. On the history of the CN Tower ( Memento from May 11, 2008 in the Internet Archive )
  11. Collection of facts about the CN Tower ( Memento from April 12, 2008 in the Internet Archive ) (English)
  12. ^ Nigel Hawkes: Wunderwerke , Südwest Verlag, Augsburg 1998, ISBN 3-86047-250-X , p. 108
  13. High-Performance Concrete (PDF), p. 309, last accessed on August 29, 2017
  14. ^ Greene: The CN Tower , p. 28
  15. ^ Greene: The CN Tower , p.25
  16. ^ Topping of Tower: The Antenna
  17. ^ Nigel Hawkes: Wunderwerke , Südwest Verlag, Augsburg 1998, ISBN 3-86047-250-X , p. 110
  18. Statistics on the CN Tower (English)
  19. CBC Digital Archives: CN Tower in Toronto opens to the public
  20. ^ Fulford, Robert: Accidental city: the transformation of Toronto . MacFarlane, Walter & Ross 1995, p. 32.
  21. ^ Dan Goodwin's Building Climbs
  22. a b Seven Wonders of the Modern World ( Memento from July 6, 2010 in the Internet Archive ) (English)
  23. CN Tower: History  ( page no longer available , search in web archivesInfo: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. (English), last accessed on January 3, 2010@1@ 2Template: Dead Link /  
  24. CBC Digital Archives: Taking Greenpeace's message to the skies , last accessed on September 22, 2009
  25. Ice fears keep Gardiner closed during commute ( Memento of March 11, 2007 in the Internet Archive ),
  26. Officials ponder icy problem , TheStar, March 6, 2007, accessed September 30, 2009
  27. a b c Marti, Monsch, Schilling: Ingenieur - Betonbau: Gesellschaft für Ingenieurbaukunst - Background - Reinforced Concrete - Concrete Structures , pages 194.
  28. FAQ on the CN Tower ( Memento from August 8, 2007 in the Internet Archive )
  29. Hossain Sharif (P. Eng.), Mashoud Nasseri: CN Tower ( Memento from January 19, 2012 in the Internet Archive )
  30. Gotthard Franz, Kurz Schäfer: Konstruktionslehre des Stahlbetons, Volume 2: Tragwerke , Springer-Verlag 1988, ISBN 978-0-387-52245-6 , p. 285
  31. Marti, Monsch, Schilling: Ingenieur - Betonbau: Gesellschaft für Ingenieurbaukunst - Background - Reinforced Concrete - Concrete Structures , pages 196.
  32. ^ High-Speed ​​Elevators ( Memento from September 25, 2009 in the Internet Archive ), last accessed on September 23, 2009
  33. ^ Nigel Hawkes: Wunderwerke , Südwest Verlag, Augsburg 1998, ISBN 3-86047-250-X , p. 111
  34. ^ Wine Cellar
  35. CN Tower introduces extreme new attraction
  36. Toronto opens Skywalk at the top of the television tower , Spiegel Online , May 11, 2011
  37. ^ Greene: The CN Tower , pp. 36/37
  38. Lighting Canada's National Tower ( Memento from September 25, 2009 in the Internet Archive )
  39. CN Tower: Night Lighting , accessed July 23, 2016
  40. CN Tower illuminated blue  ( page no longer available , search in web archivesInfo: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. , accessed August 6, 2013@1@ 2Template: Toter Link /  
  41. ^ What if the CN Tower caught fire?, November 11, 2000, accessed September 22, 2009
  42. Press release on the CN Tower, page 3 ( Memento from January 19, 2010 in the Internet Archive ) (PDF)
  43. von Borries, Böttger, Heilmeyer: TV-Towers - television towers, 8,559 meters in politics and architecture , pp. 123-124
  44. ^ OP Dwivedi, James Iain Gow: From Bureaucracy to Public Management: The Administrative Culture of the Government of Canada. University of Toronto Press, Toronto 1999, p. 45 ; Hédi Bouraoui: Thus Speaks the CN Tower. 2nd Edition. CNC Editions, Toronto 2014, p. 274 ; Vera Alexander: Postponed Arrivals. The Afro-Asian Diaspora in MG Vassanji's No New Land . In: Monika Fludernik (Ed.): Diaspora and Multiculturalism. Common Traditions and New Developments. Rodopi, Amsterdam, New York 2003, pp. 199–229, here p. 223 .
  45. ^ Michel catalog, Volume 1: North and Central America 2004
  46. Dar Robinson Jump off the CN Tower ( Memento from December 29, 2008 in the Internet Archive )
  47. Performance Analysis of the North American Lightning Detection Network using CN Tower Lighning Date (PDF), accessed October 29, 2020
  48. Vladimir A. Rakov, Martin A. Uman: Lightning: Physics and Effects , Cambridge University Press 2007, ISBN 978-0-521-03541-5 , page 255.
  49. ^ Time Capsule , last accessed September 23, 2009
  50. Lego world records
  51. ^ Von Borries, Böttger, Heilmeyer: TV-Towers - Fernsehtürme , page 124
  52. Press information on the history of the CN Tower, page 4  ( page no longer available , search in web archivesInfo: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. (pdf)@1@ 2Template: Dead Link /  
  53. ^ Information from the Federal Communications Commission
  54. Information on FM radio broadcasts from the Federal Communications Commission
  55. Toronto ARES Channels. Retrieved August 3, 2006 .
before Highest non-guyed structure after that
Ostankino TV tower (553 m)
Burj Khalifa

This article was added to the list of excellent articles on November 11, 2009 in this version .