Location & Lagoon : Batticaloa sits on a slender strip of land between the Indian Ocean and Batticaloa Lagoon , a vast estuarine water body covering ~11,500 ha and stretching ~56 km in length Beaches & Watersports : With calm seas, wide sandy shores at Batticaloa Beach , Kallady , Pasikudah , and Kalkudah , it’s perfect for swimming, snorkeling, and beach strolls Eco-attraction : The lagoon hosts mangroves, wildlife, birdlife, and even the famed “singing fish”—aquatic sounds heard at certain times