BT’s heritage stretches back over 170 years, with its forerunner the General Post Office (GPO) central to the UK’s communications, be it managing the rapid growth of the telephone network or delivering parcels and letters. And it’s this history of postal communications that is being celebrated in a new tourist attraction in London.

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The Postal Museum celebrates the history of the UK’s postal system, which is billed at the museum as ‘Britain’s earliest social network’.

Located in Clerkenwell, the Postal Museum tells the history of the UK postal service from its opening by King Charles I (when the cost of sending a letter was the same as 12 loaves of bread), to the first stamps and through two World Wars to modern communications networks.

Fascinating artefacts which bringing the story to life include a Bristol-to-London Mail Coach (whose drivers could fire pistols on ‘Her Majesty’s service’,) a rare Edward VIII post box and the sculpture of the Queen which has been replicated on over 220 billion stamps.

The exhibition also includes the famous K2 red call box designed by Sir Giles Gilbert Scott and the cast iron K8 call box designed by Bruce Martin. Read more about these design icons in our feature: The history of the red call box

KT post box

But the highlight of the Postal Museum is undoubtedly a trip across to the road to the Mount Pleasant engineering depot for a ride on Mail Rail.

Mail Rail is an underground network of secret tunnels which was used by the GPO to transport mail across the capital from 1927 until its closure in 2003. The line ran from Whitechapel in the East End to Paddington in the west, and for the first time, members of the public will be able ride through the tunnels in a specially designed passenger train.

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During the journey, the train stops at platforms where immersive video displays reveal the history of the GPO - including an appearance by the BT Tower. The journey lasts around 20 minutes and you can listen to stories from Ray the engineer about what went on in the tunnel.

BT Tower Mail Rail

The railway ran for 22 hours a day, and employed at its peak 220 people. The depot has been left untouched, with safety signs, lockers with employee’s belongings and even a train set which was used to practice.

The Postal Museum opens on July 28 and Mail Rail opens on September 4. For more information, including prices, visit

To find out more about the telecommunications side of the GPO’s history, visit the BT Archives whose extensive records start from 1846 with the Electric Telegraph Company and the birth of the GPO in 1870 right through the last century. The collection includes thousands of books, images and documents that tell the story of UK communications, including the British Phone Book collection.