Khao Nan National Park (อุทยานแห่งชาติเขานัน) is 30km from Amphoe Tha Sala. The park covers areas in Amphoe Tha Sala, Amphoe Sichon and King Amphoe Nop Phitam. The main topography is a high mountain range extending from Khao Luang National Park. The park itself is a watershed of many waterways. Travel from the city can be by Highway No. 401 across Khlong Klai past Ban Sa Kaeo in Amphoe Tha Sala. Upon reaching Km. 110, turn left into Ban Pak Chao and drive 15km to the park office.
The park’s main attraction is Sunantha waterfall which is a small but lovely waterfall. Water drops down a steep cliff to the pool below before flowing into Khlong Klai, the main waterway of Tha Sala. Rafting can be done in the canal when the water level is high.