The mountains around Kumano Hongu hold some of Japan’s most remarkable hot springs, long used by pilgrims to purify themselves before visiting the grand shrine. Yunomine Onsen, said to be the oldest hot spring in Japan at some 1,800 years, is a tiny village of steaming waters where Tsuboyu — a two-person rock bath in a hut over the stream — is the only bath in the world inscribed as a World Heritage Site. Nearby, Kawayu Onsen bubbles up through the gravel of a riverbed, where visitors dig their own bath, and in winter a giant public bath is bulldozed into the river.
🗓️ At a Glance
| Location | Hongu area, Tanabe, Wakayama |
| Hours | Baths vary; Tsuboyu ~6:00–20:00 |
| Admission | Tsuboyu ~¥800 (30 min slot); others vary |
| Time needed | Half day or an overnight |
| Best time | Year-round; Kawayu’s giant winter bath Dec–Feb |
What to Do
- Tsuboyu, the world’s only World Heritage bathing spot.
- Yunomine, said to be Japan’s oldest hot spring at 1,800 years.
- Kawayu, where you dig your own bath in the riverbed gravel.
- Kawayu’s giant bulldozed winter river bath (Dec–Feb).
Combine Your Visit
- Combine with Kumano Hongu Taisha nearby.
- Pair with the Kumano Kodo trails after a walk.
- Read our Wakayama overview .
Getting There
- By bus: from Kii-Tanabe or Shingu, buses serve Yunomine, Kawayu and Watarase onsen.
- Booking: Tsuboyu is used by one group at a time — take a numbered ticket on arrival.
Tips
Tsuboyu takes one small group at a time in 30-minute slots, so arrive early and take a numbered ticket from the village office — it’s tiny, rustic and unforgettable. At Yunomine you can also cook eggs and vegetables in the hot spring source; at Kawayu, bring a small shovel or use the provided ones to dig your own riverbed bath, and visit December to February for the giant open-air winter bath.
