Loaded with major ions — the essential minerals (Ca, Mg).
Buoyancy
Effortless float
LowHigh
Dense, salty water — you float without effort.
SodiumChloruresBrome
Tsubetsu Onsen is located in Tsubetsu, a town in eastern Hokkaido within reach of the extraordinary triple-lake volcanic complex of Akan-Mashu National Park, which encompasses Lake Kussharo (Japan's largest caldera lake), Lake Mashu (one of the world's clearest lakes, with visibility exceeding 40 meters), and Lake Akan (home of the marimo — spherical algae colonies recognized as a Japanese national special natural monument). The surrounding national park is one of Hokkaido's premier wilderness areas, with populations of brown bears, red foxes, Ezo deer, and the critically endangered Japanese crane inhabiting its volcanic and wetland landscapes. The onsen here provide mineral bathing enriched by the geothermal activity underlying this extraordinary volcanic lake district, offering visitors a restorative base for exploration of one of Japan's most biodiverse and scenically stunning national park environments.
Insider tip — Tsubetsu Onsen is situated in the town of Tsubetsu in eastern Hokkaido, near the scenic Lake Akan and the forests of the Kushiro wetlands region. The sodium-chloride water emerges at 42°C, providing a deep warming effect prized in Hokkaido's harsh winters. The surrounding landscape of birch forests and wetlands makes Tsubetsu a tranquil retreat away from busier tourist centers. The onsen is frequented by locals and nature lovers exploring the eastern Hokkaido wilderness.
