The BT Tower was built to carry aerials for the GPO’s (BT’s forerunner) microwave network, communicating with 130 stations around the country. The Tower could handle 40 TV channels and 150,000 simultaneous telephone connections.

The work of engineers on the 14th floor was central to its success. The floor hasn’t been used for many years, but for our ‘Secrets of the BT Tower’ series, we got exclusive access and spoke to Peter Abery, an engineer who worked there, to find out more about the work he did.

The BT Tower was one of London’s first skyscrapers, designed by Eric Bedford and G.R Yeats. Its unusual cylindrical shape was used for carrying aerials and meant that the building wouldn’t move more than 20cm in high winds.

The Tower was originally meant to be 111 metres tall, but ended up being 177 metres high and boasts 53 metres of concrete foundations through London clay.

It was originally called the Post Office Tower and was officially opened by Prime Minister Harold Wilson in October 1965. It was opened to the public a year later, by Postmaster General Tony Benn and holiday camp entrepreneur Billy Butlin, whose company operated the revolving restaurant on the 34th floor.

In 2003 the BT Tower was given Grade II listed building status, as a cultural and architectural icon.

Watch other episodes in our ‘Secrets of the BT Tower’ series

Credit: BT Archives