Fodor's Expert Review Kamuiwakka Onsen

Kamui means "spirit" or "god" in the Ainu language, and there's something wondrous, almost otherworldly, about this tumbling hot waterfall on the north shore under Io-zan (Mt. Io, as in Sulphur Mountain). Hot water rushes down the mountain through a series of multicolor falls and pools. Wear shoes that can get wet as you will scramble up over slippery rocks to a couple of pools higher upstream; the park staff are there to help you up down and caution you not to go much farther than the roped-off third pool. Access is by car or bus only (at certain times of the year) from early June to early November.