GUNMA

Shiriyaki Onsen

Soak in a Peaceful Natural Onsen

Just outside of Tokyo are countless opportunities to enjoy nature, from hiking and trekking on mountain trails and lush forests to basking in the tranquility of a secluded natural hot spring.

Onsen & Stay Nature & Views

Access

Enjoy a calming visit to a truly unique onsen deep in the countryside of Gunma.

A short journey away from the busy streets of Tokyo and through the forested landscapes of Gunma Prefecture is Shiriyaki Onsen, whose welcoming and healing waters attract visitors from far and wide. Located 800 meters beyond the famous Hanashiki Onsen, this secluded hot spring is well worth the trip. A short walk through the rustic town of Kuni, and visitors will arrive at their dreamy destination.

Shiriyaki Onsen is most well known for its natural open-air bath, “Kawa no Yu,” a wide and shallow portion of the Nagasasazawa River that is actually a hot spring. Bathers come to this spot year-round to enjoy the warm spring water, bringing with them water toys, and more. Even in the summertime, while some choose to enjoy the cooler water upstream, you will find many bathers relaxing in the hot spring.

The name of the onsen, “Shiriyaki,” literally translates to “butt roasting,” from the belief that sitting on the hot moss-covered stones in the riverbed helps cure ailments such as hemorrhoids. And while this name is certainly not glamorous, it is distinct and is believed to offer a host of health benefits due to the calcium-sodium sulfate-chloride in the water. People struggling with muscle pain, frozen shoulder, dermatitis, and more, may want to add Shiriyaki Onsen to their itinerary!

Visitors should be warned, however, that as Shiriyaki Onsen is a river, there is no access to storage areas or changing rooms, save for a public restroom nearby. In addition, most bathers wear swimsuits, so come prepared if you wish to bathe in the river! That said, the fact that this onsen is simply a river means that it is free of charge. You are welcome to enjoy the river and hot springs freely, while of course respecting other patrons and the onsen.
When you’ve soaked away your ailments, there is a roadside stop selling local delicacies and products, and historic silk farmers’ houses where you can dive into local history.
So, if you would like to try roasting your butt in this serene and secluded corner of the Kanto region and experience an onsen like no other, or if you simply need a refreshing and rejuvenating break from your travels, Shiriyaki Onsen is the place for you.

And since Shiriyaki Onsen is a rustic hot spring that makes use of a natural river, bathing may not be possible depending on the weather or the water level of the river. In addition, since bathing takes place in a natural environment, any accidents or troubles that may occur are your own responsibility. Please be aware of this.
Photo courtesy of Nakanojo Town Tourism Association

Address

Iriyama, Nakanojo Town, Agatsuma District, Gunma Prefecture

Phone number

+81-279-95-3111 (Nakanojo Town Kuni Branch) / +81-279-75-8814 (Nakanojo Town Tourism Association)

Business hours

Open year-round

WEB site

https://nakanojo-kanko.jp/en/

Digital Map