when in Mexico don't miss swimming in a cenote! This one seemed to be very unspectacular but was very enjoyable. Little bit isolated and well hidden but with only a few other people. Best part: watching about 300 bats while taking a swim.
The island is located in the nature reserve. Only 150 visitors per day are allowed to explore the island. There is a small tower from which you can see the Caribbean Sea and the Atlantic Ocean colliding. It's also a great place for snorkeling.