BT Tower forms part of the iconic London skyline. It stands177 meters tall and was opened by the General Post Office in 1966. Designed to support line-of-sight microwave aerials for TV and data signals it also had office space, viewing galleries and a rotating restaurant, the "Top of the Tower" operated by the famous camping holiday firm Butlins. The restaurant made a revolution every 22 minutes.

Construction cost £2.5million and the tower's foundations are a third as deep as the tower is tall. The narrow shape was chosen as the building was only allowed to move 25cm (10 inches) in high winds due to its microwave aerials. Entry to the building is provided by two high-speed lifts which travel at 6 metres per second, reaching the top of the building in 30 seconds. An Act of Parliament was passed to vary fire regulations, allowing the building to be evacuated by using the lifts unlike other buildings of the time. The Tower was given Grade II listed building status in 2003 which means several of the now defunct antennas located on the building cannot be removed.

Known over time as the Post Offce Tower and the British Telecom tower, it is still in use as a major communications hub. The building was closed to the public in 1980 over securtiy conerns although BT use the 34th floor restaurant for public and private functions

The provisional IRA exploded a bomb in the restaurant in 1971 - buildings and cars up to 400 metres away were damaged in the blast and some local residents reported being shaken from their beds but nobody was seriously hurt and the structure remained sound.

Until the mid-1990s, the building was officially a secret, and did not appear on maps. Its existence was finally "confirmed" by Kate Hoey, MP in 1993: "I hope that I am covered by parliamentary privilege when I reveal that the British Telecom tower does exist and that its address is 60 Cleveland Street, London."