Nahm tok Thi Loh Suh in Umphang district of Tak province is considered one of Thailand's largest and most attractive waterfalls. It is a segmented waterfall spreading out over a distance of about 475 meters and has multiple levels with a total height of reportedly somewhere around 275 meters, give or take.

Due to the travel distance involved to reach this waterfall, many visitors only arrive in the late afternoon and around sunset.

Therefore, Umphang Wildlife Sanctuary, in which the waterfall is located, offers accommodation at a camping, for those who want to witness the place at sunrise, when with the right light a rainbow makes the place even more attractive.