Phu Pha Thoep National Park Protection Unit (Huay Sing) is at Baan Nonsri, Na Si Nuan Subdistrict, Mueang, Mukdahan. The Huay Sing Reservoir is known as "Huay Sing," surrounded by mountains and forests. This shady and beautiful natural attraction is pleasant for camping activities, including various youth training programs. Huay Sing Reservoir is a border defense project for water restoring at Huay Sing River with a capacity of 0.738 million cubic meters, beneficial 1,280,000 square meters of farmland. The reservoir was built in 1986, and the water delivery system was improved in 1993. Currently, there are people in Mukdahan Province, and tourists come to relax, camp overnight, do activities together, including fishing.