Regnes said:
Prepare to spend the entire night with the lights on.
http://www.angelfire.com/trek/caver/page1.html
It's a long read but well worth it.
Way too long for what it was, in my opinion. Didn't even get to find out if there really was some sort of creature, and what it looked like or anything like that. However, the very last update mentions something about a 'Hodag' so I looked it up, and got this. http://en.wikipedia.org/wiki/Hodag
As for the OP's story, I can believe it. My friend's dad told me a story once, about how he was driving with his friends out in the country and he thinks there were some satanists doing weird stuff out there at the time, because folks in robes were out in the middle of night. Large amounts, from what he described.