The Kilab-kilab Falls is somewhere in the inland of Bohol, getting there is quite a trip, especially climbing down to the fall can be difficult. On rainy days to way down is probably to slippery. However, once you've found the place, it is a small marvel.
There is a large caves near the fall, and, since the water under the falls is fairly deep, you can jump from the top of that cave for a great splash. Another small cave is behind the waterfall itself. If you swim there, and dive under the waterfall, you can enter it.