San Blas Islands and Bocas del Toro offer the best for snorkeling on the Caribbean coast because of their great coral reefs and visibility.
Bocas del Toro is a sequence of islands or keys that are each wonderfully unique. Locals get around in dugout canoes and small motor boats.
San Blas offers excellent white sand beaches and clear waters on every island. The most preferred islands for snorkeling and scuba are Nargana, Corazon de Jesus, Wichuwala, Nalunanega o Isla del Pargo, Ailigandi, and Iskardup, where you can learn about the aborigine culture and acquire the famous hand made «Molas».
On the Pacific coast the Pearl Islands also offer some snorkeling but not as much reefs and lower visibility.