Punakha, town in the eastern Himalayas, west-central Bhutan. It lies at an elevation of about 5,000 feet (1,500 metres) above sea level at a point where several streams converge to form the Sankosh River. The town, founded in 1577, was once the capital of Bhutan. The old dzong (fortress, or castle) is on a promontory between the Pho and Mo rivers, tributaries of the Sankosh. Pop. (2001 est.) 3,477.