And down this way is where only cave explorers, water, and an actor from Lord of the Rings (if memory serves) go. The cave gets its name from the water that comes up every so often, and then drains down this way, sounding like ... the devil's arse. Cave explorers routinely trek down into the depths, plumbing quite a ways. And the slide you see was installed for a movie, I think it was Lord of the Rings.
Peak Cavern, Castleton, England, 22 June 2008