The Kalu Ganga, aptly called the "Black River”, begins its journey at the revered Adam's Peak (Sri Pada), a sacred pilgrimage site in Sri Lanka. Stretching 129km through the lush landscapes of the island's Southwestern region, this river is a vital centre of biodiversity. Along its route, it flows through the vibrant town of Ratnapura, famed as the heart of Sri Lanka’s gem industry, before reaching the Indian Ocean at Kalutara.

Kalu Ganga’s rich ecosystem is home to a remarkable array of plant and animal life. Its banks are lined with Mangroves, Ferns and flourishing aquatic plants, providing habitat for Freshwater Fish, Monitor Lizards and elegant waterbirds like Kingfishers and Herons. The surrounding forests offer refuge to Leopards, Elephants and a variety of native bird species, adding to the river’s ecological significance.