Tennen Onsen; Oki no Yu; Aquas
Oki, Fukuoka, Japan
- Location
- Oki, Fukuoka, 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
This complex in Oki, Fukuoka Prefecture, known as Tennen Onsen, Oki no Yu and Aquas, draws sodium-chloride water at 39°C, with an indoor bath, an outdoor rotenburo bath and a sauna.
Insider tip — 'Oki no Yu; Aquas' at Tennen Onsen in Oki-machi (大木町), a small Fukuoka farming town on the Ariake Sea plain. 'Oki' (大木 — big tree, but written differently than the offshore 沖) localizes the name to the great keyaki and camphor trees that mark this flat agricultural landscape. The 'Aquas' branding reflects the aquatic spa complex format popular in Fukuoka prefectural towns — multiple pool areas combining onsen and leisure bathing.
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.