Loaded with major ions — the essential minerals (Ca, Mg).
Buoyancy
Standard buoyancy
LowHigh
Soft water — natural, classic buoyancy.
BicarbonatesSodiumCalcium
Yasu, on the southeastern shore of Lake Biwa in Shiga Prefecture, is known for its Lake Biwa windsurfing culture, the Yasu River delta where reed marshes support important migratory bird populations, and the traditional lakeshore fishing culture of the Biwako communities that has sustained this coastal settlement across many generations of Japanese history. Yasu Onsen Shiga draws on sodium and bicarbonate thermal waters from the geothermal resources of the Lake Biwa basin, providing restorative baths in a lakeside setting where views across Japan's largest freshwater lake and the distant Hira Mountains create a profoundly serene natural panorama. The Lake Biwa Museum in nearby Kusatsu, the historic Karasaki pine tree of Otsu's Tanka poetry tradition, and the easy access to both Kyoto via the Biwako Line and the Shiga nature trail cycling network make Yasu an attractively located spa destination on Lake Biwa's southern shore.
Insider tip — Yasu sits on the eastern shore of Lake Biwa, Japan's largest freshwater lake, where the Suzuka and Hira mountain ranges descend steeply to the water's edge. The thermal waters here emerge from the ancient metamorphic basement rocks of the Shiga highlands, producing smooth bicarbonate baths favored by Kyoto and Osaka residents seeking a countryside retreat. Bathers in lakeside facilities enjoy panoramic views across Lake Biwa, whose shifting light and seasonal storms create a dynamic scenic backdrop. The lake cycling route passes directly through town, making Yasu a natural rest stop for cyclists completing the full 200-kilometer circuit.