Photo: 交通アキ② · CC BY-SA 4.0 · Wikimedia Commons

Kaiōizumi Onsen

Yamanashi · 甲斐大泉温泉

Kaiōizumi Onsen is a hot spring town in Yamanashi, Japan. The water leaves the ground at 52°C, hot. It measures pH 7.5 — close to neutral. Officially the water is classed as chloride spring, bicarbonate spring and iron spring. Its sources put out around 177 litres a minute.

Getting there

From Tokyoabout 2½ h

CarNot needed

JR PassCovers the train

Train to Kai-Ōizumi Station (JR)
A short walk

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 springBicarbonate springIron 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.

Bicarbonate spring 炭酸水素塩泉

Smooth, slightly slippery water. Often nicknamed bihada-no-yu, the water for beautiful skin.

Iron spring 含鉄泉

Turns reddish brown as the iron meets air. The water is clear at the source.

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 — Yamanashi Inns with a private bath — Yamanashi