Phu Pha Yon in Ban Na Phang village, Khok Pla Sio subdistrict, Mueang district is 38 kilometers away from the downtown area of Sakon Nakhon. Located within the compound of a monastery, Phu Pha Yon features rock engravings about the lifestyle of Thai community in prehistoric period. The 3,000-year-old petroglyphs were created by using solid tools to incise or carve part of a rock surface to form the shapes of men, animals, people and farm cattle, geometric shapes, palms, crop fields, etc. Visitors can reach there from Tao Ngoi district via the Tao Ngoi – Si Wicha route for 5 kilometers. Then use Highway 2339 to enter Ban Muang – Na Ang. Continue onto Ban Phon Bok – Phon Phang and Ban Na Phang respectively for 35 kilometers. Just before arriving at Phu Pha Yon, there is an asphalt road stretching to the rock cliff and a flight of stairs containing 238 steps. A number of viewpoints which are made from piles of stone dot along the way. Some look like small sheds, while others look like benches.