Below pavement level: wartime bunkers, installations, burial crypts, dug-up plague pits, sewers, excavated Roman walls, remnants of Henry VIII's tennis courts, poncy wine cellars, bunkers, London, and forgotten corners of the Tube. Ghost stations unused since the 1930's, "fluffers " that used to clean the Underground of all its hair, discarded wallets, and nail clippings... Having read a couple of books on underground Britain, I won't be joining the SubBrits. But those dark underground passage-ways, and forgotten histories, are fascinating. Just the London Tube for instance.... One of those threads that can flourish, or crash, or have its secrets heavily edited. Worth a punt?