Ive been about 15 years ago, twice actually. Best snorkeling trip ive ever been on there. Took us to 3 different places, one of them being a freshwater diving hole, another one some caves. As close to dying as ive ever been came on one of those trips on a two lane highway and our van driver tried to pass another car with a car coming head on. I have no clue how all 3 cars squeezed on that road.