Loaded with major ions — the essential minerals (Ca, Mg).
Buoyancy
Standard buoyancy
LowHigh
Soft water — natural, classic buoyancy.
CalciumSulfatesMagnésium
Phu Sang National Park in Phayao province, northern Thailand, features a remarkable natural thermal cascade where hot calcium-rich water flows over a cliff face, creating a dramatic hot waterfall that plunges into a cool stream below — one of the rare places in the world where visitors can simultaneously experience hot geothermal water and cold mountain runoff. The park's combination of this unique thermal phenomenon, diverse tropical forest, and mountain scenery makes it one of northern Thailand's most memorable natural attractions. The remote location near the Myanmar border adds to its sense of genuine adventure and discovery.
Insider tip — Phu Sang National Park's hot waterfall in Phayao Province is a rare sight where calcium-rich thermal water at 35°C cascades over an active travertine formation, depositing creamy white mineral crust year by year. The waterfall is one of only a few naturally hot cascades in Southeast Asia and the resulting limestone terrace resembles a miniature Pamukkale. The surrounding national park protects old-growth teak forest and wild orchid populations. The cool highland air at 600 m elevation makes the lukewarm waterfall surprisingly refreshing rather than scalding.
