I just read this story of a caver and his unusual and very spooky experience. It's extremely well-written, perfect foreshadowing, fantastic use of good old-fashioned psychological suspense. It's even got illustrating photographs.

For what it's worth, I believe that while the cave is real and the photographs are from one or more legitimate caving expeditions, the, uhm, extra additives in the story are probably fiction. At least... I hope that's the case....

Okay, have done some investigation. Yes, it's fiction, and apparently based on a short story by Thomas Lera called "The Fear of Darkness" (you can download a copy of the original story in PDF format, if you like). And while in the process of researching I came across Dionaea House, a similar story written in blog format. Very interesting. (I found that blog via Exploring Hyperfiction, a really interesting site in its own right).