I used to go to this place all the time a few years ago, but back then there was no way to get in. I went back two days ago and voila no roof, so I climed in. It was definitely one of the most interesting places I've explored, it went like 3 levels underground. I didn't venture down to the last level because there was about 6 inches of water covering the floor and I only had converse on. I plan on going back when I have more time to explore, and with rain boots.