The entrance of the cavern is on a sandy floor at 18m deep. When you go inside, the cave go down to 21m and then become smaller. There is a marlin skeleton inside (put there by a resort diver!)
If you follow the left hand side of the cavern you will end up in front of a tunnel. The tunnel connects "turtle cavern" with "turtle tumb" a small cave system which contains many turtle skeletons. The turtles have drowned inside because they couldn't find their way out. Since this could happen also to a diver, I would recommend to go in there only with a local guide.
Since many divers have got lost in the tunnels of the cave, nowadays all the dive centers request all divers to have the PADI Specialty of Cave Diving.