Aira-shi Onsen Center; Ryumontaki Onsen
Aira, Kagoshima, Japan
- Location
- Aira, Kagoshima, Japan
- Water type
- thermal, sodium chloride
- Temperature
- 41 °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
Aira-shi Onsen Center; Ryumontaki Onsen is located in Aira, Kagoshima Prefecture. The sodium-chloride thermal water reaches 41°C. Indoor bath, outdoor bath (rotenburo) and sauna round out the facility.
Insider tip — 'Ryumontaki Onsen' (龍門滝 — dragon gate waterfall) at Aira-shi Onsen Center in Aira city. Aira sits on the northern rim of the ancient Aira Caldera — one of Earth's most violent prehistoric eruptions (29,000 BP), whose AT ash layer is found across East Asia. Today's Kinkowan Bay is the caldera's flooded remnant, with Sakurajima as its regenerated cone. The hydrothermal system feeding this onsen is a direct legacy of that cataclysm.
Nearby
Frequently asked questions
How hot is the water?
The water runs quite hot here, around 41 °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.