There is a cave system that has to be visited. Its turned a little touristy with the a tram that takes you up the mountain and a restaurant and gift shop at the top. But the cave it self is untouched. Its a wonderful tour. For the more extreme there is an advanced path but you have to prove you can do it with a replica of the smallest point called the keyhole. Its no mean feat.
If you can ignore the obvious touristy face, you can really enjoy a good spelunking.