Sasou Onsen
- Location
- Sasou, Iwate, Japan
- Water type
- bicarbonate, carbonated
- Temperature
- 38 °C
- pH
- 6.3
Water profile
Soothing — neither hot nor cold, perfect balance.
Loaded with major ions — the essential minerals (Ca, Mg).
Mineralised water — eases movement and joints.
Sasou Onsen—Beckoning Spring—takes its name from the Japanese verb sasou, meaning to invite, beckon, or coax into accompaniment, a name that frames the thermal spring as an entity with its own inviting presence—a spring that calls the traveler toward it through the promise of warmth, mineral renewal, and the particular pleasure of volcanic water that seems to actively beckon the weary body into its embrace. The bicarbonate and carbonated waters deliver an effervescent, skin-stimulating mineral soak that justifies the spring's beckoning name with its lively, engaging mineral character—a spring whose CO2 effervescence creates the tactile excitement of natural carbonation on the skin that most directly rewards those who accept the invitation to enter. Rising in Iwate Prefecture's volcanic landscape, this beckoning spring invites visitors into a thermal experience of genuine geological animation and mineral richness.