BT Tower

The BT Tower in London, England, previously the Post Office Tower and also the London Telecom Tower, is a tall cylindrical building at 60 Cleveland Street in Fitzrovia. The main structure is 175 metres (574 feet) tall, with a further section of aerial bringing the total height to 188 metres (620 feet).

The tower was commissioned by the General Post Office (GPO).

Its primary purpose was to support the microwave aerials then used to carry telecommunications traffic from London to the rest of the country.

The tower was designed by the architects of the Ministry of Public Building and Works: the chief architects were Eric Bedford and G. R. Yeats. Typical for its time, the building is concrete clad in glass. The narrow cylindrical shape was chosen because of the requirements of the communications aerials: the building will shift no more than 25 cm (10 inches) in wind speeds of up to 150 km/h (95 mph). Initially the first sixteen floors were for technical equipment and power, above that was a 35 metre section for the microwave aerials, and above that were six floors of suites, kitchens, technical equipment and finally a gridwork aerial. To prevent heat build-up the glass cladding was of a special tint.

The construction cost was £2.5 million.

Construction began in June 1961. The tower was topped out on July 15, 1964 and it was operational from October 8, 1965. The building contractors were Peter Lind & Company.

The tower was officially opened to the public on May 16, 1966 by Tony Benn and Billy Butlin. As well as the communications gear and office space there were viewing galleries, a souvenir shop, and a slowly rotating restaurant, the “Top of the Tower”, on the 34th floor, operated by Butlins. It made one revolution every 22 minutes. An annual race up the stairs of the tower was established and the first race was won by UCL student Alan Green.

A suspected IRA bomb exploded in the roof of the men’s toilets at the Top of the Tower on October 31, 1971 and it was subsequently closed to the public for security reasons. The restaurant closed in 1980 when Butlins’ lease expired and non-BT-approved access to the building ceased. In 1981 it was superseded as the tallest building in Britain by the NatWest Tower (renamed Tower 42).