Sai-no-Kawara Outdoor Bath

A popular open air bath in Kusatsu with an area of 500㎡!

Sai-no-Kawara Park, at Kusatsu Onsen, has a huge outdoor bath in the back. You can enjoy the waters while viewing the scenery all throughout the four seasons, such as the new greenery in the spring, the beautiful foliage in the fall and the snowscape in the winter.
Business Hours
Saturday ( 9:0 AM ~ 8:0 PM )
Sunday ( 9:0 AM ~ 8:0 PM )
Weekdays ( 9:0 AM ~ 8:0 PM )
Adult: 600 JPY
Children: 300 JPY

Re-opened on May 30th 2015 after restoration.
Sai No Kawara Outdoor bath,521-3 Kusatsu Kusatsucho Agatsuma-gun Gunma
(0279) 88-6167


Relax your entire body in the outdoor bath that resembles a pond

A 10-minute walk away from Kusatsu’s symbolic Yubatake, when you pass the tourist-friendly Sai-no-Kawara Avenue with its manju (bean paste-filled cakes) and souvenir shops, you will end up at a desolate and dry river bed with lava rumbling underneath and smoke rising. This is Sai-no-Kawara Park where 1400 liters of 50-degree C water gushes out every minute from along the Yukawa River. Due to the high acidity of the water, there is no plant life on the river bed. There is stone paving within the park for ease of walking, and there are also beautifully shining onsen ponds of emerald green such as Zuisho Pond and Kohaku Pond. And there is Anamori-Inari Shrine with its attractive red torii gates. The sand on the shrine grounds is known as “lucky sand” and if some of it is taken back and spread out at certain places, it will bring good fortune. At the very back of the park is Sai-no-Kawara Outdoor Bath. Including the men’s and women’s bathing areas, it is an open-air bath that measures 500㎡ and is popular for its spaciousness. Crowding at this pond-like bath is irrelevant. Bathing here while viewing the surrounding mountains and trees is the greatest. You will want to keep on visiting the bath with the fall foliage, the winter snow and the star-filled skies at night. The source spring has clear hot water with a greenish hue, and within Kusatsu Onsen, it is a high-temperature spring that is close to the lava. The water gushes forth at a temperature of 94 to 95 degrees C so cooler water is added but even so the water is very salty to the taste reflecting the high salt concentration. The bath is of a kakenagashi (flowing water) style, so if you go to the back and the steam lifts, you can see an onsen waterfall. It is not a place to enjoy a bath to wash your body, but it is the perfect bath to recover from fatigue and forget the hustle and bustle of the day.

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