Editing BT Tower (section)

==History==
===Design and construction===
The tower was commissioned by the [[General Post Office|GPO]]. Its primary purpose was to support the [[microwave]] [[Antenna (electronics)|aerials]] then used to carry telecommunications traffic from London to the rest of the country, as part of the [[General Post Office microwave network|GPO microwave network]].<ref>''Belfast Telegraph'' Thursday 2 February 1961, page 10</ref>

It replaced a shorter, 1940s steel [[lattice tower]] on the roof of the neighbouring Museum Telephone Exchange. The taller structure was required to protect the radio links' [[line of sight]] against tall buildings then planned in London. Links were routed via GPO microwave stations [[Harrow Weald]], [[Bagshot]], [[Kelvedon Hatch]] and [[Wrotham transmitting station|Fairseat]], and locations including the [[London Terminal Control Centre|London Air Traffic Control Centre]].{{cn|date=January 2025}}

[[File:cmglee BT Tower.jpg|thumb|Wide-angle view of the tower and its base from Cleveland Mews in August 2012]]

The tower was designed by the [[Ministry of Works (United Kingdom)|Ministry of Public Building and Works]], under chief architects [[Eric Bedford (architect)|Eric Bedford]] and G R Yeats. Typical for its time, the building is concrete clad in glass. The narrow cylindrical shape was chosen as a stable platform for microwave aerials. It shifts no more than {{convert|25|cm|in|0}} in wind speeds of up to 150&nbsp;km/h (95&nbsp;mph). To prevent overheating, the glass cladding had to be tinted.{{cn|date=January 2025}}

Construction began in June 1961; owing to the building's height and its having a tower crane [[Jib (crane)|jib]] across the top virtually throughout the whole construction period, it gradually became a very prominent landmark that could be seen from almost anywhere in London. A question was raised in Parliament in August 1963 about the crane. [[Reginald Bennett]] MP asked the [[First Commissioner of Works|Minister of Public Buildings and Works]], [[Geoffrey Rippon]], how, when the crane on the top of the new Tower had fulfilled its purpose, he proposed to remove it. Rippon replied: "This is a matter for the contractors. The problem does not have to be solved for about a year but there appears to be no danger of the crane having to be left in situ."<ref>{{Cite web |date=2 August 1963 |title=Post Office Tower (Crane) |url=https://api.parliament.uk/historic-hansard/written-answers/1963/aug/02/post-office-tower-crane#S5CV0682P0-03632 |access-date=21 January 2015 |website=[[Hansard|Parliamentary Debates (Hansard)]]}}</ref> Construction reached 475 ft by August 1963. The revolving restaurant was prefabricated by [[Ransomes & Rapier]]<ref>''Daily Herald'' Friday 1 November 1963, page 8</ref> and the lattice tower by [[Stewarts & Lloyds]] subsidiary Tubewrights.<ref>''Birmingham Daily Post'' Wednesday 7 October 1964, page 7</ref>

The tower was [[topped out]] on 15 July 1964, by Geoffrey Rippon<ref>''Coventry Evening Telegraph'' Wednesday 15 July 1964, page 40</ref> and inaugurated by Prime Minister Harold Wilson on 8 October 1965. The [[General contractor|main contractor]] was [[Peter Lind & Company]].<ref>{{Cite web |title=BT Tower |url=http://www.lightstraw.co.uk/ate/main/postofficetower/index.html |access-date=21 January 2015 |website=lightstraw.co.uk |archive-date=27 July 2019 |archive-url=https://web.archive.org/web/20190727151218/http://www.lightstraw.co.uk/ate/main/postofficetower/index.html |url-status=dead }}</ref>

The tower was originally designed to be just {{convert|111|m|ft|0}} high; its foundations are sunk down through {{convert|53|m|ft|0}} of [[London clay]], and are formed of a concrete raft {{convert|27|m|ft|0}} square, {{convert|1|m|ft|0}} thick, reinforced with six layers of cables, on top of which sits a reinforced concrete pyramid.<ref>"BT Tower: serving the nation 24 hours a day", BT, 1993</ref>

Initially, the first 16 floors were for technical equipment and power. Above that was a {{convert|35|m|ft|adj=on}} section for the [[microwave]] aerials, then six floors of suites, a revolving restaurant, kitchens, technical equipment, and finally a [[cantilever]]ed steel lattice tower. The construction cost was £2.5 million.{{cn|date=January 2025}}

The first microwave link was to [[Norwich]] on 1 January 1965. The [[Met Office]] put a weather radar on top of the tower.<ref>''Liverpool Echo'' Thursday 1 October 1964, page 8</ref> Much of the telecommunications equipment was made by [[General Electric Company|GEC]].<ref>''Coventry Evening Telegraph'' Friday 8 October 1965, page 63</ref> The stainless steel clad windows were made by [[Henry Hope & Sons Ltd]].<ref>''Birmingham Daily Post'' Monday 26 July 1965, page 24</ref>

===Opening===
[[File:HM the Queen visiting the Post Office Tower on 17 May 1966.jpg|thumb|left|[[Queen Elizabeth II]] visiting the tower in May 1966]]
The tower was opened to the public on 19 May 1966, by [[Postmaster General of the United Kingdom|Postmaster General]], [[Tony Benn|Anthony Wedgwood Benn]] and [[Billy Butlin]],<ref>Archived at [https://ghostarchive.org/varchive/youtube/20211211/Fx7S2ZLwvo8 Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20140419081321/http://www.youtube.com/watch?v=Fx7S2ZLwvo8&gl=US&hl=en Wayback Machine]{{cbignore}}: {{Cite web |title=Post Office Tower Opening (1966) |url=https://www.youtube.com/watch?v=Fx7S2ZLwvo8 |access-date=20 October 2018 |website=YouTube | date=13 April 2014 |publisher=British Pathe}}{{cbignore}}</ref><ref>{{Cite web |title=Post Office Tower – 18 May 1966, Volume 728 |url=https://hansard.parliament.uk/Commons/1966-05-18/debates/d4cd9526-de56-4297-ad55-4717f62d4b96/PostOfficeTower |access-date=20 October 2018 |website=Hansard |publisher=Parliament |archive-date=21 October 2018 |archive-url=https://web.archive.org/web/20181021024817/https://hansard.parliament.uk/Commons/1966-05-18/debates/d4cd9526-de56-4297-ad55-4717f62d4b96/PostOfficeTower |url-status=live }}</ref> with [[Elizabeth II|HM Queen Elizabeth II]] having visited on 17 May 1966.<ref>Archived at [https://ghostarchive.org/varchive/youtube/20211211/EK-3H9yEIro Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20140419193940/http://www.youtube.com/watch?v=EK-3H9yEIro&gl=US&hl=en Wayback Machine]{{cbignore}}: {{Cite news |date=17 May 1966 |title=Queen Enjoys View From The Top |url=https://www.youtube.com/watch?v=EK-3H9yEIro |access-date=20 October 2018 |agency=British Pathe}}{{cbignore}}</ref>

As well as communications equipment and office space, there were viewing galleries and a souvenir shop. [[Butlins]]' Top of the Tower [[revolving restaurant]] on the 34th floor made one revolution every 23 minutes<ref>{{Cite web |title=Look at Life - Eating high, 1966 |url=https://www.youtube.com/watch?v=FMPXmnK8G8E&t=142 |website=[[YouTube]] |date=September 2011 |access-date=4 November 2018 |archive-date=1 June 2022 |archive-url=https://web.archive.org/web/20220601091022/https://www.youtube.com/watch?v=FMPXmnK8G8E&t=142 |url-status=live }}</ref><ref>''Liverpool Daily Post'' Wednesday 3 June 1964, page 14</ref> and meals cost about £4<ref>''The Tatler'' Saturday 17 September 1966, page 51</ref> ({{Inflation|UK|4|1966|fmt=eq|cursign=£|r=-1}}{{Inflation/fn|UK}}).

In the first year there were nearly one million visitors,<ref name="btplc.com">{{Cite web |title=Events in telecommunications history |url=https://www.btplc.com/Thegroup/BTsHistory/1912to1968/1965.htm |url-status=dead |archive-url=https://web.archive.org/web/20181020182102/https://www.btplc.com/Thegroup/BTsHistory/1912to1968/1965.htm |archive-date=20 October 2018 |access-date=20 October 2018 |publisher=BT plc}}</ref> and over 100,000 diners.<ref>{{Cite news |last=Glancey |first=Jonathan |date=7 October 2005 |title=The great communicator |url=https://www.theguardian.com/artanddesign/2005/oct/07/architecture |access-date=20 October 2018}}</ref>

===Bombing===
A bomb exploded in the ceiling of the men's toilets at the Top of the Tower restaurant at 04:30 on 31 October 1971,<ref name="btplc.com" /> the blast damaged buildings and cars up to {{convert|400|yds|m}} away.<ref>{{Cite news |date=31 October 1971 |title=1971: Bomb explodes in Post Office tower |url=http://news.bbc.co.uk/onthisday/hi/dates/stories/october/31/newsid_2464000/2464143.stm |access-date=16 June 2021 |publisher=[[BBC News]] |language=en-GB |archive-date=7 March 2008 |archive-url=https://web.archive.org/web/20080307113253/http://news.bbc.co.uk/onthisday/hi/dates/stories/october/31/newsid_2464000/2464143.stm |url-status=live }}</ref> Responsibility for the bomb was claimed by members of [[the Angry Brigade]], a far-left [[anarchist]] collective.<ref>{{Cite web |title=Bangor Daily News |url=https://news.google.com/newspapers?nid=2457&dat=19711102&id=ICs0AAAAIBAJ&sjid=G-EIAAAAIBAJ&pg=3240,422159&hl=en |access-date=21 April 2016 |website=news.google.com |via=Google News Archive Search}}</ref> A call was also made by a person claiming to be the Kilburn Battalion of the [[Irish Republican Army|IRA]].<ref>{{Cite news |date=3 April 2007 |title=BBC ON THIS DAY – 31 – 1971: Bomb explodes in Post Office tower |url=http://news.bbc.co.uk/onthisday/hi/dates/stories/october/31/newsid_2464000/2464143.stm |access-date=31 December 2009 |publisher=BBC News |archive-date=7 March 2008 |archive-url=https://web.archive.org/web/20080307113253/http://news.bbc.co.uk/onthisday/hi/dates/stories/october/31/newsid_2464000/2464143.stm |url-status=live }}</ref>

The tower for visiting was closed to the general public following the 1971 bombing, but the restaurant reopened. In 1980, Butlins' restaurant lease expired.<ref>{{Cite web |date=16 August 2010 |title=BT Tower to open for first time in 29 years |url=https://www.theregister.co.uk/2010/08/16/bt_tower/ |website=theregister.co.uk |access-date=10 August 2017 |archive-date=10 August 2017 |archive-url=https://web.archive.org/web/20170810173032/https://www.theregister.co.uk/2010/08/16/bt_tower/ |url-status=live }}</ref>

The tower has been used for events including a children's Christmas party and [[Children in Need 2010]]. It retains the revolving floor.{{cn|date=January 2025}}

===Recent===
The tower's microwave aerials remained in use into the 21st century, connected to [[Subterranean London|subterranean]] [[optical fibre]] links.{{cn|date=January 2025}}

{{Wide image|BT Tower Evening Panorama 2014-03-05 18.30.jpg|2120px|Panoramic view from BT Tower in the evening, 2014.}}

In 2009, a 360° coloured screen was installed {{convert|167|m|ft|abbr=on}} up,  over the 36 and 37th floors of the tower. It replaced an earlier light projection system and incorporated 529,750 [[LED]]s arranged in 177 vertical strips around the tower. It was then the largest of its type in the world,<ref>{{Cite web |date=31 October 2009 |title=BT Tower of power: World's biggest LED screen set to light up the night |url=http://crave.cnet.co.uk/televisions/0,39029474,49304098,00.htm |url-status=dead |archive-url=https://web.archive.org/web/20091102034258/http://crave.cnet.co.uk/televisions/0,39029474,49304098,00.htm |archive-date=2 November 2009 |access-date=31 October 2009}}</ref> occupying an area of {{convert|280|m2|sqft|sigfig=1|abbr=on}} and with a circumference of {{convert|59|m|ft|abbr=on}}. It displayed a countdown of the number of days until the start of the [[2012 Summer Olympics]].{{cn|date=January 2025}}

In April 2019, the screen broadcast a [[Windows 7]] error message for almost a day.<ref>{{Cite web |last=Thomson |first=Iain |title=BT Tower broadcasts error message to the nation as Windows displays admin's shame |url=https://www.theregister.co.uk/2019/04/08/bt_tower_broadcasts_error_message_to_the_nation_as_windows_crashes/ |access-date=15 April 2019 |website=www.theregister.co.uk |archive-date=18 April 2019 |archive-url=https://web.archive.org/web/20190418010719/https://www.theregister.co.uk/2019/04/08/bt_tower_broadcasts_error_message_to_the_nation_as_windows_crashes/ |url-status=live }}</ref>

[[File:BT Tower, London 13 January 2023.jpg|thumb|right|The tower's LED screen]]

In October 2009, ''[[The Times]]'' reported that the revolving restaurant would be reopened in time for the 2012 London Olympics.<ref name="Goodman">{{Cite news |last=Goodman |first=Matthew |date=1 November 2009 |title=High times as BT reopens its revolving restaurant |url=http://www.timesonline.co.uk/tol/life_and_style/food_and_drink/eating_out/article6898128.ece |access-date=27 April 2010 |work=The Times |location=London}}{{dead link|date=September 2024|bot=medic}}{{cbignore|bot=medic}}</ref> However, in December 2010, it was noted those plans had been "quietly dropped".<ref>{{Cite web |date=20 December 2010 |title=BT Tower Restaurant Won't Re-Open |url=http://londonist.com/2010/12/bt-tower-restaurant-wont-re-open.php |access-date=21 January 2015 |website=Londonist |archive-date=21 January 2015 |archive-url=https://web.archive.org/web/20150121074527/http://londonist.com/2010/12/bt-tower-restaurant-wont-re-open.php |url-status=live }}</ref>

{{Wide image|London panorama from the BT Tower.jpg|2560px|360° panoramic view from the revolving restaurant in September 2022.}}

For the tower's 50th anniversary, the 34th floor was opened for three days from 3 to 5 October 2015 to 2,400 winners of a lottery.<ref name="50 ingenious years">{{Cite web |title=Celebrating BT Tower's 50 ingenious years – come and visit the top of the BT Tower! |url=http://home.bt.com/news/bt-life/BT-Tower-event-11363983181830?s_cid=con_FURL_BTcom_BTTower50 |url-status=dead |archive-url=https://web.archive.org/web/20170620224249/http://home.bt.com/news/bt-life/BT-Tower-event-11363983181830?s_cid=con_FURL_BTcom_BTTower50 |archive-date=20 June 2017 |access-date=6 October 2015}}</ref>

[[File:BT Tower, London, 15 March 2011.jpg|thumb|BT Tower at night, 2011]]

The BT Tower was given Grade II [[listed building]] status in 2003.<ref>{{Cite news |date=26 March 2003 |title=Honour for Post Office Tower |url=http://news.bbc.co.uk/2/hi/uk_news/england/2886617.stm |access-date=16 June 2021 |publisher=BBC News |language=en-GB |archive-date=24 June 2021 |archive-url=https://web.archive.org/web/20210624195701/http://news.bbc.co.uk/2/hi/uk_news/england/2886617.stm |url-status=live }}</ref> Several of the defunct antennae attached to the building were protected by this listing, meaning they could not be removed unless the appropriate listed building consent was granted. Permission for their removal was given in 2011 on safety grounds, as they were in a bad state of repair and the fixings were no longer secure.<ref>{{Cite news |date=30 August 2011 |title=London's BT Tower to lose dish-shaped aerials |url=https://www.bbc.co.uk/news/uk-england-london-14721413 |access-date=30 August 2011 |publisher=BBC News |archive-date=28 April 2012 |archive-url=https://web.archive.org/web/20120428073908/http://www.bbc.co.uk/news/uk-england-london-14721413 |url-status=live }}</ref> The last of the antennae was removed in December 2011, leaving the core of the tower visible.<ref>{{Cite news |title=Engineers remove microwave dishes from the BT Tower in London |url=https://www.telegraph.co.uk/news/picturegalleries/uknews/8937926/Engineers-remove-satellite-dishes-from-the-BT-Tower-in-London.html |access-date=8 April 2023 |work=The Telegraph |archive-date=8 April 2023 |archive-url=https://web.archive.org/web/20230408092514/https://www.telegraph.co.uk/news/picturegalleries/uknews/8937926/Engineers-remove-satellite-dishes-from-the-BT-Tower-in-London.html |url-status=live }}</ref>

Entry to the building is by two high-speed lifts, which travel at a top speed of 1400 feet per minute ({{convert|7|m/s|mph|sigfig=3}}) and reach the top of the building in under 30 seconds.  The original equipment was installed by the [[National Lift Tower|Express Lift Company]], but it has since  been replaced by elevators manufactured by [[ThyssenKrupp]]. Due to the confined space in the tower's core, removing the motors of the old lifts involved creating an access hole in the cast iron shaft wall, and then cutting the 3-ton winch machines into pieces and bringing them down in one of the functioning lifts.<ref>{{Cite web |title=BT TOWER LIFT REMOVAL |url=https://www.liftout.net/liftout-bt-tower/ |access-date=22 February 2024 |website=Liftout - Corporate Site |archive-date=22 February 2024 |archive-url=https://web.archive.org/web/20240222161714/https://www.liftout.net/liftout-bt-tower/ |url-status=live }}</ref>  In the 1960s an [[Act of Parliament (UK)|Act of Parliament]] was passed to vary fire regulations, allowing the building to be evacuated by using the lifts&nbsp;– unlike other buildings of the time.<ref>{{Cite web |title=London Telecom Tower |url=http://www.urban75.org/london/telecom.html |access-date=18 March 2011 |archive-date=8 November 2020 |archive-url=https://web.archive.org/web/20201108125429/http://www.urban75.org/london/telecom.html |url-status=live }}</ref>

In 2006, the tower began to be used for short-term air-quality observations by the [[UK Centre for Ecology & Hydrology]] and this has continued in a more permanent form as BT Tower Observatory, an urban atmospheric pollution observatory to help monitor air quality in the capital.<ref>{{Cite web |last=Helfter |first=Dr Carole |date=28 June 2018 |title=BT Tower (London, UK): an urban atmospheric pollution observatory |url=https://www.ceh.ac.uk/our-science/projects/bt-tower-london-uk-urban-atmospheric-pollution-observatory |access-date=10 November 2020 |website=UK Centre for Ecology & Hydrology |archive-date=21 June 2020 |archive-url=https://web.archive.org/web/20200621151327/https://www.ceh.ac.uk/our-science/projects/bt-tower-london-uk-urban-atmospheric-pollution-observatory |url-status=live }}</ref><ref>{{Cite web |date=14 January 2019 |title=Research provides quality check on air pollution strategy |url=https://www.ceh.ac.uk/news-and-media/blogs/research-will-provide-quality-checks-air-pollution-strategy |access-date=10 November 2020 |website=UK Centre for Ecology & Hydrology}}</ref> The aim is to measure pollutant levels above ground level to determine their source. One area of investigation is the long-range transport of fine particles from outside the city.<ref>{{Cite web |title=BT Tower in pollution study |url=http://www.btplc.com/Innovation/News/tower.html |access-date=8 November 2007}}{{dead link|date=July 2021|bot=medic}}{{cbignore|bot=medic}}</ref>

On 21 February 2024, BT Group announced the sale of BT Tower to [[MCR Hotels]], who plan to retain the tower as a hotel.<ref name="Kolirin 2024 m662">{{Cite web |last=Kolirin |first=Lianne |date=21 February 2024 |title=The BT Tower, London's futuristic landmark, to become hotel |url=https://www.cnn.com/2024/02/21/travel/londons-iconic-bt-tower-to-become-hotel-intl-scli-gbr/index.html |access-date=21 February 2024 |website=CNN |archive-date=22 February 2024 |archive-url=https://web.archive.org/web/20240222004451/https://www.cnn.com/2024/02/21/travel/londons-iconic-bt-tower-to-become-hotel-intl-scli-gbr/index.html |url-status=live }}</ref><ref>{{Cite news |last=Laursen |first=Christian Moess |title=BT Group Sells London's BT Tower for $347 Million to MCR Hotels |url=https://www.wsj.com/business/telecom/bt-group-sells-londons-bt-tower-for-347-million-to-mcr-hotels-57fd5b02 |access-date=2024-02-21 |work=WSJ |language=en-US |archive-date=21 February 2024 |archive-url=https://web.archive.org/web/20240221103245/https://www.wsj.com/business/telecom/bt-group-sells-londons-bt-tower-for-347-million-to-mcr-hotels-57fd5b02 |url-status=live }}</ref><ref>{{Cite web |last=Warren |first=Jess |date=21 February 2024 |title=BT Tower: 'Iconic' landmark to be turned into a hotel after £275m sale |url=https://www.bbc.co.uk/news/uk-england-london-68352275 |access-date=21 February 2024 |website=BBC News |archive-date=21 February 2024 |archive-url=https://web.archive.org/web/20240221101102/https://www.bbc.co.uk/news/uk-england-london-68352275 |url-status=live }}</ref>