The westernmost range is separated from the Tenasserim coast by the Three Pagodas Fault. West of it lie the Dawna Range, the Karen Hills and the valleys of the Salween and the Gyaing. Southwards on the western side, the Ye, Heinze, Dawei (Tavoy), Great Tenasserim (Tanintharyi) and the Lenya rivers are relatively short and flow into the Andaman Sea. Further south the Kraburi River forms the southern border between Thailand and Burma.