Shiranui Onsen; Roman no Yu
Uki, Kumamoto, Japan
- Location
- Uki, Kumamoto, Japan
- Water type
- thermal, sodium chloride
- Temperature
- 39 °C
- pH
- 7.3
Water profile
Thermicity
Sedative
LowHigh
Relaxing — deep, immediate muscle release.
Mineralisation
Restorative
LowHigh
Loaded with major ions — the essential minerals (Ca, Mg).
Buoyancy
Effortless float
LowHigh
Dense, salty water — you float without effort.
SodiumChloruresBrome
Shiranui Onsen, also called Roman no Yu, sits in Uki, Kumamoto Prefecture. Its sodium-chloride thermal water measures 39°C. The bathhouse offers an indoor bath, an outdoor rotenburo bath and a sauna.
Insider tip — 'Roman no Yu' (ロマンの湯 — romantic spring) at Shiranui Onsen in Uki city. 'Shiranui' (不知火) are the mysterious phosphorescent lights seen on the Yatsushiro Sea on August nights — mirages created when warm air meets cool seawater, appearing as floating flames. These apparitions have inspired Japanese poetry, mythology and the naming of countless local businesses since ancient times. A bath beside these legendary mysterious waters has a romantic logic all its own.
Nearby
Frequently asked questions
How hot is the water?
The water runs quite hot here, around 39 °C — a sedative water that brings immediate muscle release.
What type of water is found here?
This spot features thermal & sodium chloride water.
What is the best season to visit?
The most favourable period for this spot is: Toute l'année.