Miizumi Jozan (1805–1877) was a Japanese Buddhist monk of the Sōtō Zen sect who is revered as the founding father of Jozankei Onsen. In 1866, guided by local Ainu people, he encountered the healing thermal springs in the upper reaches of the Toyohira River. Despite the rugged, pathless wilderness, Jozan established a small spa to treat the sick and wounded, laying the foundation for what would become Hokkaido's most famous hot spring town.