Rich in active gases or metals — a strong mineral character.
Buoyancy
Standard buoyancy
LowHigh
Soft water — natural, classic buoyancy.
SoufreSulfuresSulfates
Ashiyu Hakuba Happo Onsen sits in Hakuba, in the mountains of Nagano Prefecture. Its sulfurous thermal water, with a pH of 6.5, emerges at 42°C (108°F). An indoor bath, an outdoor rotenburo bath and a sauna are available on site.
Insider tip — Hakuba Happo-One hosted the 1998 Nagano Winter Olympics alpine skiing events and is Japan's largest ski resort, with the snow-plastered Northern Alps behind as backdrop. The ashiyu (free foot bath) at Happo Onsen lets visitors — skiers, hikers, and cyclists — warm cold feet for free while enjoying Hakuba Valley views. Happo-One's July–August alpine flower meadows are as spectacular as the winter skiing; combine with a soak at one of the valley's many ryokan onsens after a day on the slopes.