We went on a full day tour by Price Riviera to the Sian Ka'an nature reserve. It is a huge lagoon with fresh and salt water areas. We saw dolphins, a crocodile, a sea turtle, mangroves, and many birds including storks, cormorants and frigate birds. Part of the trip was on an open truck and some in a boat. We went swimming on a natural beach and had lunch in the small Mayan fishing village Punta Allen. Our guide was very knowledgeable and was fluent in four languages. Overall it was an exciting day.