Nestled in a narrow, forested valley around a rapidly flowing river, Yunomine is said to be one of Japan's first onsen towns — people have been soaking here for over 1,800 years. The village is picture-perfect: traditional wooden buildings line the riverbanks, steam rises from vents in the road, and the mineral-rich water has turned the river rocks a surreal shade of white and orange. It's connected to Hongu by a steep 3.5-kilometre trail that pilgrims have walked for centuries, or a 20-minute bus ride for those who prefer their hot springs without a preamble of sweat.