Manas River flows in Bhutan and is the largest river system of Bhutan. Three other river systems of Bhutan are Torsa, Wong, Sankosh. It is met by three other major streams before it again debouches into India in western Assam.
After flowing a total of 376 kilometers, it meets Brahmaputra River at Jogighopa. Its river valley is home to Royal Manas National Park in Bhutan and the contiguous Manas Wildlife Sanctuary of India which is a Project Tiger Reserve, an Elephant Reserve and a Biosphere Reserve as well as a UNESCO World Heritage Site.