For over 1000 years, people have made pilgrimage to the onsen to participate in hot spring water purification rituals to prepare for visiting Kumano Hongu Taisha shrine to worship.

The World Heritage site of Tsuboyu Bath; a small, wooden cabin houses a stone-lined hot spring.

Several kabuki plays refer to the Tsuboyu bath[3] including the tale of “Oguri Hangan and Princess Terute”, in which the former is healed from a debilitating illness.

[6] Legends claim that the thermal spring water was found flowing out of a stone statue of Yakushi Nyorai, the Buddha of healing and medicine.

[4] Yunomine Onsen/Tsuboyu Bath is the only hot spring that is featured as part of the UNESCO World Heritage pilgrim route, Kumano Kodo.