Since you can't place caches in caves this proved the next best thing for a ring depository. See if you can find the one ring to rule them all! Fun location but not for the faint of heart or for that matter the claustrophobic. Should accommodate most adults and children. Be sure and avail yourself of the other nearby caches, that's how I found this spot in the first place and now you can try for the bonus (GC57G90) by solving the field puzzle located at this cache.
As always cache in trash out! Be safe, don't do anything you don't feel comfortable with and good luck!
P.S. I would love feedback on the helpfulness of hints, the accuracy of ratings or anything else that you can think of that would improve the experience for those after you