Tokusa Onsen

Mountain onsen at the headwaters of Lake Yunoko inside Nikkō National Park, 1500 m above the temples of Nikkō. Cloudy sulfur springs in a primeval beech forest.

Quiet gorge onsen at the confluence of the Kinu and Kawaji rivers in Tochigi, just upstream of bustling Kinugawa. The local saying "Kawaji for cuts, Kinugawa for ailments" nods to its gentle alkaline waters and traditional yutoji feel.

Tochigi resort town in the Kinugawa River gorge — gateway to Nikko and a long-time family destination, with cliff-top rotenburo overlooking the canyon.

A hamlet on the Tadami River in Oku-Aizu with one bathhouse and one minshuku, sharing a 38 °C spring so charged with dissolved carbon dioxide that it ranks among the most carbonated in Japan — tea-brown, faintly salty, lukewarm enough to sit in for an hour, and drunk as well as bathed in. A second spring rises cold a few minutes away: a well of natural sparkling water that Meiji-era traders shipped to Europe and that is still bottled today.