One station and a short section of tunnel are opening in 2017 as part of the Postal Museum. I forget all the detail, but the main limitation as to how far acces

One station and a short section of tunnel are opening in 2017 as part of the Postal Museum. I forget all the detail, but the main limitation as to how far access is allowed is all down to the fact that evacuation was scarcely considered for the tunnels, given it wasn't really designed to carry passengers.