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Acidic hot springs

67 acidic-water places mapped worldwide. Find where to soak — and where to stay nearby.

Hotels in Japan →See the springs ↓

What is acidic water?

Characterized by a high concentration of Hydrogen ions (H⁺) and often a pH < 3.0. This acidity gives an invigorating sensation and a felt natural "peeling" effect on the skin.

The water is so active it can sting ("Piri-piri"). A short bath is recommended.

pH
Very Acidic (< 3.0)
Family
Cation (+)
Element
H⁺ · pH < 3
Origin
Active volcanism (dissolving sulfurous gases)
Best for
Invigorating sensation & volcanic curiosity
Temperature
Often very hot

What it feels like

The extreme acidity gives an invigorating sensation and a felt natural "peeling" effect on the skin (a short bath is recommended).

Sensations & traditions

Did you know — Tamagawa Onsen in Japan has a pH of 1.2, as acidic as gastric juice! Knives rust there overnight.
Good to know — Sensitive skin, Open wounds, Elderly/weak individuals (short bath recommended).

Wellness and cultural information — no therapeutic claims. If in doubt, ask a healthcare professional.

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67 acidic springs to explore

Frequently asked questions

What is acidic water?
Characterized by a high concentration of Hydrogen ions (H⁺) and often a pH < 3.0. This acidity gives an invigorating sensation and a felt natural "peeling" effect on the skin. The water is so active it can sting ("Piri-piri"). A short bath is recommended.
What does a acidic-water bath feel like?
Invigorating sensation ("piri-piri"). A felt natural "peeling" effect. Rare and spectacular volcanic waters.
Where can I find acidic hot springs?
Thermae lists 67 acidic-water places worldwide, including Tamagawa Onsen (Japan), Sukawa Onsen (Japan). Explore the map to filter them by country and destination.
Are there any precautions with acidic water?
Sensitive skin, Open wounds, Elderly/weak individuals (short bath recommended). Wellness and cultural information — no therapeutic claims. If in doubt, ask a healthcare professional.

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