Kanneliya-Dediyagala-Nakiyadeniya, or KDN, is a forest reserve in the Southern Province of Sri Lanka. Identified as one of the most floristically rich areas in South Asia; this forest region is the last remaining large rainforest in Sri Lanka, other than the Sinharaja Rainforest. The forest is situated 35km northwest of the City of Galle; and is a major catchment area for two of the most important rivers in southern Sri Lanka, Gin Ganga and Nilwala Ganga. Designated as a biosphere reserve in 2004 by UNESCO, the Kanneliya forest reserve home to many endemic plant and animal species.
The KDN forest reserve consists of a series of parallel hills and valleys; ranging in elevation from 60m to 425m above sea level, and extending to an area of approximately 5306 hectares. It acts as a catchment for many rivers and streams; including Gin Ganga and Nilwala Ganga, that have their sources within the forest, and flow toward the west and the east of the forest respectively. Kanneli (from which Kanneliya gains its name), Nanikiththa and Udugama are the smaller streams that begin within the Kanneliya Rainforest; while Homa Dola and Gal Bandi Dola are sourced by the Nakiyadeniya and Dediyagala and pass through the forest. The forest receives a substantial rainfall of 3,750mm; with a mean annual temperature of 27.0°C, which can vary approximately 4°C to 5°C. Many ancient taxonomic groups of Gondwana are present in these rain forests. They also relate to Indo-Malayan plants and animals.
