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The Island of St. Martins is the only coral island in Bangladesh located in the north-eastern parts of the Bay of Bengal. The roughly flat island is only about 3-6 metres above the sea level. The entire island can be walked about in 3 hours. The island is known for its unique natural beauty with white sandy beaches fringed with coconut palms and a diverse marine life. Due to the expansion of unregulated tourism, the island is facing increasing erosion, contamination of surface and ground water, wildlife displacement, and loss of biodiversity. Other threats include cutting of sand dune vegetation for fuel-wood and hotel establishment; degradation of sand dune habitat; the harvesting of turtle eggs; indiscriminate exploitation of coral resources etc. To address this, the Government has declared some areas of the island as Ecologically Critical Area (ECA), prohibiting unauthorized constructions there.