Loaded with major ions — the essential minerals (Ca, Mg).
Buoyancy
Standard buoyancy
LowHigh
Soft water — natural, classic buoyancy.
BicarbonatesSodiumCalcium
Omitama, in central Ibaraki Prefecture on the Kanto Plain, is an agricultural city set amid the broad open farmlands of the Ibaraki interior where lotus root, sweet potato, and rice cultivation define the rural character of this Kanto agricultural heartland between the Tone and Naka rivers. Omitama Onsen Ibaraki draws on sodium and bicarbonate thermal waters from the deep sedimentary geological formations of the north Kanto aquifer, providing warm therapeutic baths for local residents in a pleasantly unhurried agricultural community removed from the suburban pressures of the greater Tokyo zone. The flat cycling countryside of Omitama's surrounding farm districts, the nearby Kasumigaura lake shore — the second-largest lake in Japan — and the distinctive Ibaraki agricultural market culture of seasonal vegetable and flower festivals create a quietly rewarding natural backdrop for thermal bathing in this central Ibaraki farming community.
Insider tip — Omitama occupies the flat Kanto lowlands of central Ibaraki, where bicarbonate-rich thermal water at 40°C is pumped from sedimentary strata beneath the patchwork of rice paddies and melon fields. The town was formed from a merger of three former municipalities and retains a dispersed rural character, making its sento a genuine local meeting point. Ibaraki's melon-growing fame extends to Omitama, and seasonal produce stalls near the bathhouse entrance are a charming local detail. The water's high bicarbonate content gives a particularly smooth skin feel distinct from the saltier coastal wells.