The Thi Lo Su Waterfall is claimed to be the largest and highest waterfall in Thailand. It stands 250 metres (820 ft) high and nearly 450 metres (1,480 ft) wide on the Mae Klong River, flowing down from Huai Klotho into the Umphang Wildlife Sanctuary in Tak Province in northwestern Thailand.
The most famous water fall in Tak is, Namtok Thi Lo Su ( Thi Lo Su waterfall ) is located in the Umphang Wildlife Sanctuary, a UNESCO World Heritage site, which links with the Thung Yai Naresuan and Huay Kha Kaeng Reserves, as well as Khlong Lan and Mae Wong National Parks. Together, they form Thailand's largest wildlife haven and one of Southeast Asia's few virgin forest.