A century ago traffic congestion on London’s streets was at breaking point and letters were arriving late.
The problem got so bad that by 1915 the Post Office started to dig tunnels as part of an ambitious scheme to build a fast rail network which would carry letters underground.
It ran from east to west for 80 years using miniature trains. Although it was forbidden, it’s an open secret that staff, family and friends often used the trains to catch a lift across London alongside the post.
Now the public can try it too. The train is part of the UK’s first Postal Museum which opens this week.