Saint Martin Island, the only Coral Island of Bangladesh- is inhabited by 7 to 8 thousand of people. Most of them are depended on fishing or fishing related activities. There are beautiful corals on the southern corner of the island. Chera Dwip, another small island should be visited on your trip by the boat. The water is much clearer here compared to another beach. It is possible to snorkeling here if you carry your own equipment. It is fantastic if you stay there during the full moon time.