The Gulf of Mannar marine National Park, about 10 km away from the east coast of Tamil Nadu, consists of 21 small islands (islets) and coral reefs in the Gulf of mannar in the Indian Ocean. The core area of Gulf of Mannar Biosphere Reserve lies between Thoothukudi (Tuticorin) and Dhanushkodi.
The national park is picturesque for its rich confluence of estuaries, mudflats, beaches and forests. The lush green islands are dominated by mangroves, though flowering herbs, sea grass and seaweeds are abundant.
The Dugong, a vulenrable marine mammal is the most important inmate of the park. The park is also home to Indo-Pacific hottlenose dolphin, finless porpoise, spinner dolphin and common dolphin. About 510 of the 2,200 fin fish species in Indian waters are found in the Gulf of Mannar, making it the most highly diverse fish habitat in India.
The islands in the Gulf of Mannar are uninhabited and access is prohibited. Tourists visiting the marine national park can use glass-bottomed boats to see the marine splendor abundant in this area.
Visiting the islands in dependent on permission received from the Chief Conservator of Forests and Chief Wild Life Warden. Accommodation and hotels are available both in Rameswaram and Ramanathapuram.