Photo: Ruess1 · CC BY-SA 4.0 · Wikimedia Commons
Yudanionsen
Yudanionsen is a hot spring town in Toyama, Japan. The water leaves the ground at 39°C, comfortably warm. It measures pH 9.5 — strongly alkaline. Officially the water is classed as chloride spring and sulfur spring. Its sources put out around 202 litres a minute.
The water here
Chloride spring
Salty water. The salt leaves a thin film on the skin, so you stay warm well after leaving the bath.
Sulfur spring
The classic rotten-egg smell and milky white water. It can tarnish silver jewellery, so take it off.
Things to see nearby
Places from Wikidata, photographs from Wikimedia Commons. Distances are in a straight line from the town.
With tattoos
Many public baths still turn away visible tattoos, and the rule is set by each bath, not by the town. The reliable way round it is to bathe privately: a room with its own open-air bath, or an inn with a private bath you can book for yourselves.
Where to stay
Hot spring towns nearby
Similar water elsewhere
The numbers
- Water temperature
- 39°C
- pH
- 9.5 (strongly alkaline)
- Discharge
- 202 litres a minute
- Address in Japanese
- 富山県砺波市庄川町湯谷
Figures from the town's Japanese Wikipedia article.
Where it is
36.5596, 137.0064 — open the map
Read more
Planning a first soak? Read how an onsen stay works, and what to do if you have tattoos.