Photo: おにく · CC0 · Wikimedia Commons

Kusatsu Onsen

Gunma · 草津温泉

Kusatsu Onsen is a hot spring town in Gunma, Japan. The water leaves the ground at 44.9–94.5°C, hot enough that it has to be cooled before anyone can get in. It measures pH 1–2.2 — strongly acidic, the kind that stings on a cut. Officially the water is classed as chloride spring, sulfate spring, acidic spring and sulfur spring. Its sources put out around 32,300 litres a minute. 171 inns take visitors here with room for about 12,531 guests. About 3.27 million people a year come to bathe.

Getting there

From Tokyoabout 3 h

CarNot needed

JR PassCovers the train

Train to Naganohara-Kusatsuguchi Station (JR)
Local bus

Fly into Haneda or Narita. Times are rough estimates worked out from station locations, not a timetable — check the exact route on Google Maps.

Chloride springSulfate springAcidic springSulfur spring

The water here

Chloride spring 塩化物泉

Salty water. The salt leaves a thin film on the skin, so you stay warm well after leaving the bath.

Sulfate spring 硫酸塩泉

Clear water with a faintly bitter taste. Known for holding heat.

Acidic spring 酸性泉

Strongly acidic, sometimes below pH 2. It stings on cuts and is not for long soaks.

Sulfur spring 硫黄泉

The classic rotten-egg smell and milky white water. It can tarnish silver jewellery, so take it off.

More photographs

From Wikimedia Commons. Tap a photo for the photographer and licence.

Things to see nearby

Kusatsu Onsen Ski ResortSki area · 1.2 km

Ōsen FallsWaterfall · 2.4 km

Jōfu FallsWaterfall · 3.8 km

Kōsen-ji TempleTemple · 0.2 km

Omote Manza Snow ParkSki area · 6.4 km

Agatsuma GorgeGorge · 13 km

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.

Rooms with an open-air bath — Kusatsu Town Inns with a private bath — Kusatsu Town