It may come as a surprise, but London Underground doesn’t have the only underground railway network in the nation’s capital.

Running directly under the feet of millions of unsuspecting Londoners and passing many of the city’s most recognisable landmarks, the Post Office Underground Railway – Mail Rail – ran between 1927 and 2003 from Whitechapel in the east to Paddington in the west. Shut down over a decade ago, the world’s first driverless, electrified railway has been frozen in time – until now.

As part of plans for the Postal Museum, a new national museum coming to central London in 2016, the British Postal Museum & Archive (BPMA) intends to open up Mail Rail. A loop of the old railway that runs under and around the Mount Pleasant sorting office has been leased for a period of 25 years.

Some changes – new entrances and fire escapes – will have to be built in order to open the railway up to the public. However, to create a permanent record of Mail Rail as it is now, and was the day it was closed in 2003, the BPMA has been exploring

the use of 3D data capture. ScanLab Projects, a 3D scanning and visualisation company based in East London, has produced some impressive imagery that shows Mail Rail in a way that isn’t possible through traditional 2D photography and enhances understanding and appreciation of the space.

The data collected not only forms a detailed record of Mail Rail before construction but could also be used in many ways to further improve the visitor experience. For example, the use of virtual reality technology could enable a full 3D walkthrough of hidden parts of the network or an app that enables layers to be peeled away to see the original industrial detail beneath.

Mail Rail should be open to the public sometime in 2016.