An "architectural icon of Harold Wilson's 'white heat of technology'"The BT Tower - one of London's most prominent landmarks - has today been given listed building status by arts minister Tessa Blackstone, along with six other "historically and architecturally outstanding" communications structures around the country. According to the government, each structure is a landmark of its type and together the buildings illustrate the rise of what it describes as "vital new British communications technology" in the 1950s and 60s. The decision to list the structures was taken on the advice of English Heritage, which put together its recommendations as part of a study of post-war communications buildings. Baroness Blackstone, Minister of State for the Arts, said in a statement: "Our built heritage should be about much more than old buildings. The best of our modern architecture also merits the recognition and protection that listing brings." She added: "Structures like the BT Tower and the ntl Broadcasting Tower [on Emley Moor, Yorkshire] are cultural and architectural icons of Harold Wilson's 'white heat of technology'. These buildings mark the early milestones of Britain's transformation into one of the most technologically advanced nations in the world today." Sir Neil Cossons, chairman of English Heritage, said: "Britain was a world leader in telecommunications during the 1950s and 1960s, and these seven new listings are a tribute to that scientific achievement as well as being architectural icons of the times. Listing will not impede the buildings' continued scientific work." Listing a building should ensure that care is taken over decisions affecting its future, that any alterations respect the particular character and interest of the building, and that the case for its preservation is taken fully into account in considering the merits of any redevelopment proposals. The BT Tower was the first purpose-built structure to transmit high frequency radio waves. It was designed to allow for the rapid expansion of telephone communications and to overcome the difficulty of laying cables in London. To preserve the accuracy of the sensitive narrow-beam transmitters they had to be sited on a stable structure - the cylindrical shape of the tower reduced wind resistance. The tower, incorporating observation galleries and a restaurant, stands at 620ft above street level, including the 40ft London Weather Centre radar mast. A terrorist bomb led to the closure of the observation galleries in 1971, while the restaurant closed in 1980 when the owner's lease expired. It has subsequently been refurbished and is now used for corporate entertainment. The other five buildings listed today are: Equatorial Telescopes, Herstmonceux, East Sussex; Lighthouse, Dungeness, Kent; British Telecom Earth/Satellite Station Antenna No.1, Goonhilly Downs, Cornwall; Radar Training Station, Fleetwood, Lancashire; County Police Communication Tower, Aykley Heads, Durham.