Mountain Open-Air Baths: The Three Hot Springs of Kumano Hongu

Overview

Kumano Hongu Onsen-go is not one resort but three hot-spring hamlets in the mountains of Tanabe, close to the Kumano Kodo trails that converge on Kumano Hongu Taisha; all three can be visited in a day. Yunomine is the oldest: tradition dates its discovery to the fourth century and calls it Japan’s oldest hot spring, and pilgrims once bathed here in purification before taking the Dainichi-goe path to Oyunohara, the shrine’s former site. Its rock pool, Tsuboyu, is inscribed as part of the Kumano Kodo World Heritage — the water is said to change colour seven times in a day — and opens from 6am to 9pm. In the stream outside, the yuzutsu vent runs at around 90°C, hot enough to boil an egg.

Kawayu is stranger still. The Otogawa (大塔川) runs past the inns, and water of roughly 70°C rises through its gravel bed, so bathers dig a hollow in the stones and temper it with river water to make a bath of their own. From December to the end of February the riverbed is dammed to create the Senninburo, a broad open-air bath held near 40°C and open from 6.30am to 10pm, with lanterns lit along it on Saturday evenings. In poor weather a plain communal bathhouse stands in the middle of the hamlet, open 6.30am to 8pm and closed on Tuesdays.

Watarase, on the Yomura river below the Kumano mountains, is the gentlest of the three: a colourless sodium-bicarbonate spring long known as a bijin-no-yu, or beauty bath. Watarase Onsen has one of the largest free-flowing open-air baths in the Kansai region, with private baths that day visitors can book, and opens 6am to 10pm. Next door, the bathhouse at WATAZE OUTDOOR sits inside a campsite and cottage ground, open to day guests from 10am to 8pm, closed Thursdays.