We took a tour here that we booked through our hotel for 475 pesos per person. I would recommend going to the dock where you can get a boat over to the island yourself! It's way cheaper and you can figure out everything to do there without a guide. Our package included snorkeling (but you can rent the gear yourself, which we still had to pay for separately), lunch (which was ok-- i would have rather picked a restaurant there myself) and seeing the crocodiles by the dock where you leave from (which you can totally check out on your own). The snorkeling is really good! Bring crackers so you can feed the fish and they will swarm around you! They are beautiful! The water is calm and warm.
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