I can't remember where I took the picture but the door was numbered 48. These doors always make me curious as to seeing what's behind them, but I've never been around when anyone comes out of them. This one was particularly scary as there's not only a deep pit but a void behind it too.
I've just finished re-reading Neverwhere for my book group and one of the main characters is door-opener called Door (funnily enough). She travels from a parallel London called London Below to London Above (the London we know). In the London Below some of the characters (including the Earl from Earl's Court) live in those darkened "Special" Tube trains which always speed past your stop and live on Choclit & Coke from the platform vending machines.
But I imagine even Door would think twice about opening the door above. If anyone has been around to see what's behind them please let us know. Hopefully it's not the fire and brimstone or deep pits full of weird underworld creatures that I imagine.