The Salween (, , also spelt Thanlwin; , ; , Gyalmo Ngulchu; , literally "Angry River" in Chinese — the river is actually named after the Nu people living in the area, but Chinese having no phonetic script had to use a character with a similar sound as Nu which happens to be the character for rage; Thai , Mae Nam Salawin ; is a river, about long, that flows from the Tibetan Plateau into the Andaman Sea in Southeast Asia. It drains a narrow and mountainous watershed of that extends into the countries of China, Burma and Thailand. Steep canyon walls line the swift, powerful and undammed Salween, one of the longest free-flowing rivers in the world. Its extensive drainage basin supports a biodiversity comparable with the Mekong and is home to about 7 million people. In 2003, key parts of the mid-region watershed of the river were included within the Three Parallel Rivers of Yunnan Protected Areas, a UNESCO World Heritage Site.