In north and west Kanchanaburi Province, the terrain is comprised mainly of mountains and high plains, with the Thanon Thongchai Range acts as a natural border between Thailand and Myanmar. The range is the source of Kanchanaburi’s two most important rivers Maenam Khwae Noi (Little Kwai River) and Maenam Khwae Yai (Big Kwai River), which form the famous Maenam Mae Klong. As a result of these major rivers and three of Thailand’s largest reservoirs, Kanchanaburi features several of Thailand’s largest Namtok (waterfalls) as well as a number of wildlife sanctuaries.