Unlike its neighbour Hirauchi, this blissfully serene seaside onsen can be entered at any tide, making it far less stressful to plan around. You'll walk 300 metres from the bus stop through a tiny village, passing a magnificent banyan tree en route, before reaching the open-air pools beside the sea. The setting is achingly peaceful — just you, the warm mineral water, and the sound of the Pacific. It's the quieter, more contemplative sibling of Yakushima's coastal hot springs.