The map may help you to work it out, we sell a large paper version at Michael's Bookshop in Ramsgate, this come rolled up in a tube and is too difficult and too expensive to post.
here is the link to the tunnels website
space invader urbex
Here at Michael's Bookshop, where I pretend to work in Ramsgate it's been a fairly quiet day and I have been catching up with correspondence. Because tomorrow is Thursday the bookshop will be closed.
link to the photos of the books we put out today