Dad Hot Spring, formerly called Kui Mang. It was accidentally discovered by Japanese soldiers who were supervising the construction of the Death Railway. The natural hot spring features two large pools and private baths. The mineral in the spring is believed to cure many diseases, e.g. beriberi (lack of vitamin B), arthritis, etc. Visit to Pha Tad Waterfall located in the western zone of Si Nakharin Dam National Park. It originates from a small stream called Huai Kui Mang.