The phantom hitchhiker is frequently attached to Bluebell Hill in Kent, between Rochester and Maidstone. On the old road, not the dual carriageway.

And underneath the old Crystal Palace site in South London, there has been reported to be a train buried in a tunnel, full of skeletons. My friend spoke to the girl who fell into the tunnel, so it must be .... well, she couldn't show him the hole, and her original description that the skeletons were all sitting upright changed when he pointed out some boring facts about anatomy. Anyway, the tunnels there run all the way to Dover under the North Downs, and part of the way there, there is a bottomless well (this is rural, not urban), and they know it is bottomless because they unround a reel of binder twine down it, and it just kept on and on unwinding to the end of the reel without stopping. The whole planet must be full of tunnels and holes.