The waters in Costa Rica are not very clear for snorkeling. There are only a couple of very good spots where people could enjoy beautiful coral reefs. One of those spots is Cahuita National Park. Specifically for scuba diving, the two best sports in the country are: Caño Island and Coco`s Island. Some other spots are Playas del Coco and Monkey Head, and Cahuita.
Coco`s Island is knonw internationally for its shark population. The only way to visit the island is on a private cruise on a 7 days period. On the other hand, Caño Island is visited for its beutiful tropical marine life in turquois waters. It also has a very interesting archeological site.