Vegetarian's Japan Guide

Kawarayu Onsen: A New Hot Spring Town With a Long History

Kawarayu Onsen in Agatsuma District in Gunma Prefecture is a hot spring town almost one thousand years old. It was first discovered in 1193 by Japan’s first shogun, Minamoto no Yoritomo (源頼朝), the founder of the Kamakura shogunate. Due to Kawarayu Onsen’s close proximity to Kusatsu Onsen, the town thrived as its Agariyu (上がり湯), where tourists would stop by to help their skin recover from Kusatsu’s strong acidic hot spring.

However, since its completion in late 2019, the Kawarayu Onsen has become a part of Yamba Dam (八ッ場ダム). Fortunately, thanks to a newly discovered hot spring source, the hot spring town has been relocated to the dam lake’s shore! So if you love hot springs, how about visiting this newly created onsen town with a long history?

The Attractions in Kawarayu Onsen

Kawarayu Onsen Play Base NOA (川原湯温泉あそびの基地NOA)

Just in front of JR Kawarayu Onsen Station, Kawarayu Onsen Play Base NOA is a multi-purpose leisure facility equipped with a campground, a public bathhouse, and a cafe. It also offers barbeque facilities and various water activities/tours at Yamba Dam Lake. If you haven’t got anything planned for the day, the tourist information counter on the first floor can be of great help.

© 川原湯温泉あそびの基地NOA
© 川原湯温泉あそびの基地NOA

The campsite and the barbeque facility are just by the lake shore. The best thing about Kawarayu Onseneki Campsite is the tents and everything else are set up for you. Depending on the plans chosen, you can even come empty-handed!

If you are a vegan/vegetarian, it is best to bring your favorite vegetables or mushrooms.

Kawarayu Onseneki Campsite’s Hot Spring Facility and Available Services

© 川原湯温泉あそびの基地NOA

An advantage of renting a campsite in a hot spring town is you can enjoy both the outdoor adventurous vibe and the nice onsen. When you need to rejuvenate, head to Sasayu (笹湯) to indulge in Kawarayu Onsen’s hot spring. Although it isn’t a free facility, the cost is quite reasonable. The hot spring at Sasayu is continuously sourced from the hot spring source. Since it’s not circulated, chemicals to disinfect the water aren’t used.

Note: Only soap is available. It is best to bring your own towel and toiletry set.

Besides the public bathhouse, renting a wood-fired outdoor bath and a sauna tent is also possible.

Tip: You will get a discount for Sasayu’s admission fee if you also rent out the tent site or barbeque facility.

Kawarayu Onsen Play Base NOA also offers bicycle rental services. Instead of relying on your foot, how about renting a bicycle and cycling between Kawarayu Onsen’s attractions?

If you love water sports, you can either join a SUP, a canoe tour, or rent the equipment from the facility.

For more information about the facility, refer to the official website HERE and translate it using Google Chrome’s translation function at the right of the address bar.

  • Sasayu is open from 12 pm to 6 pm.
    • The last admission is at 5 pm.
  • The admission cost to Sasayu is
    • 990 yen for adults
    • 440 yen for elementary school students and younger
  • Coin-operated lockers are available. It costs 100 yen per use.
  • The bicycle rental service is available from 10 am to 4:30 pm.
  • The cost of a bicycle rental is 1,000 yen for 2 hours or 2,000 yen per day.

Kawarayu Shrine (川原湯神社)

Kawarayu Shrine is the guardian shrine of the hot spring town. Initially, the sacred site was a temple built above Kawarayu Shrine’s spring sauce, enshrining the Healing Buddha. Magically, its new location is also next to Kawarayu Onsen’s newly discovered onsen source!

© 長野原町役場

You might notice the building is relatively new compared to other shrines in Japan. While the shrine already existed in the Edo period, it suffered from repetitive fire hazards, including the last time it burnt down in 2001.

Instead of reconstructing the shrine in its original location, it was built at the hot spring town’s new location in 2017. This is why it is weirdly sandwiched between the motorway and the embankment of the mountain.

Although the torii gate and the shrine building were lost in the fire hazard in 2001, the stone Buddha and God statues lining the approach were carved hundreds of years ago.

How to Get to Kawarayu Shrine

  • Kawarayu Shrine is a 10-minute walk from JR Kawarayu Onsen Station (川原湯温泉駅).

Ōyu Hot Spring (王湯)

Ōyu is one of the three public bathhouses in the old Kawarayu Onsen and is the only public bathhouse that was relocated. Whether you are after a hot spring session or not, visit it as a symbol of the hot spring town. It is also where you can see the Minamoto family crest formed by bamboo grass and gentians (笹竜胆).

© 長野原町役場

The onsen in the bathing tub is a neutral spring with a pH of 7.2 and is gentle on the skin. Although it has a light sulfur smell like Kusatsu Onsen, you can soak in the onsen for an extended amount of time without hurting your skin.

It is said that the hot spring here is good for neuralgia, rheumatism, gastrointestinal diseases, women’s diseases, and more. As the landmark of Kawarayu Onsen, people would visit Ōyu even if their ryokan has a hot spring facility!

Ōyu’s location is superb. From the outdoor hot spring pool, you can adore the stunning Yamba Agatsuma Lake (八ツ場あがつま湖) and the mountains surrounding it.

Note that the hot spring tubs are small. The open-air tub has a capacity of around 5 people, and the indoor pool can fit around 10 people. So on weekends and public holidays, you might need to wait for the shower facility and even to enter the hot spring pools.

☛ Small free coin-operated lockers are available. The larger ones aren’t free.
☛ There is a spacious tatami mat-covered resting room on the second floor for you to chill after a hot spring session.
☛ Vending machines selling drinks and snacks are available.

Ōyu Hot Spring’s Business Hours, Admission Fees, and Access Information

  • Ōyu is open from 10 am to 5:30 pm (the last admission).
    • It is closed on the 1st and the 20th of January.
  • The admission fee for a 2-hour hot spring session is
    • 500 yen for adults
    • 300 yen for children
  • Kawarayu Shrine is a 15-minute walk from JR Kawarayu Onsen Station (川原湯温泉駅).

Roadside Station Yamba Furusato-kan (道の駅 八ッ場ふるさと館)

Roadside Station Yamba Furusato-kan also has a foot spa. If you need a towel to dry your feet afterwards, it can be purchased from the roadside station.

© 長野原町役場

If you plan to drive from Kusatsu Onsen, the Roadside Station Yamba Furusato-kan is located at Kawarayu Onsen’s entrance. Like other roadside stations in Japan, you can source fresh ingredients and local specialties here (sweet cabbage is recommended).

The roadside station also sells freshly baked bread. If you eat eggs and dairy, get a Damyaki (ダム焼き). The dam-shaped cake has either custard cream or red bean paste. The Asama Kogen Milk Soft Serve (浅間高原牛乳ソフト) is another must-try if you are a sweet tooth.

For a special souvenir, get a pack of Shio Ama Nattō (塩あま納豆). Scarlet runner bean (Hanamame, 花豆) is Gunma Prefecture‘s specialty. The confectionery made using the beans is commonly found in Gunma, but you can hardly find the salted sweetened dried beans.

Besides shopping and dining, you can also collect the Yamba Dam card from the roadside station. The card has the dam’s image printed on one side and its profile on the other.

Moreover, electric-assisted bicycles can be rented from Roadside Station Yamba Furusato-kan between 9 am and 4:30 pm. The cost of a bicycle rental is 1,000 yen for 2 hours or 2,000 yen per day. You can also return the bicycle to Kawarayu Onsen Play Base NOA.

Refer to HERE for the recommended route.

Roadside Station Yamba Furusato-kan’s Opening Hours and Access Information

  • The farmer’s market is open from 8:30 am to 6 pm (to 5 pm in winter).
  • The free foot spa is open from 6 am to 9 pm.
  • The tourist information counter is open from 9 am to 5 pm.
  • The restaurant is open from 9 am to 6 pm. Note the broth/sauce used isn’t vegetarian.

Fudoo Bridge (不動大橋) and Fudō Falls (不動の滝)

Fudoo Bridge is one of the three bridges as a part of Yamba Dam’s construction. The 590-meter-long bridge is the world’s first extradosed bridge using steel and concrete composite truss.

Coming from the Roadside Station Yamba Furusato-kan, the 90m Fudō Falls and Yamba Agatsuma Lake (八ツ場あがつま湖) from Fudoo Bridge are the first two natural scenic views of the hot spring town. The waterfall usually has a significant amount of water coming down the cliff. Although it is hard to tell from Fudoo Bridge, the Fudō Falls is a three-tier waterfall. The part of the Fudō Falls that is visible from the bridge is the bottom part of it.


The contrast between the red leaves and the white waterfall is stunning in autumn. In winter, the Fudō Falls will likely become an icefall, giving you another reason to visit Kawarayu Onsen. As Fudō Falls and Fudoo Bridge are within walking distance from JR Kawarayu Onsen Station (川原湯温泉駅) and the hot spring town, stop by during your stay!

On the other end of Fudoo Bridge, there is a small temple called Kawarayu Fudōdō (川原湯不動堂), enshrining the Fudō Myōō (不動明王) or Immovable Wisdom King in English. If you plan to drive, the temple’s small parking lot has a capacity of 3 cars.

Kawarayu Fudōdō has more than 700 years of history. It was relocated from the old Kawarayu Onsen site. From the temple, you can also view the Fudō Falls from nearby. Inside the temple, there are many swords and tin plates. They were offered by pilgrims in the Meiji and Shōwa periods to pray for victory in wars.

Yamakikan (山木館)

One thing that many international tourists would love to experience in Japan is staying at a traditional ryokan. When you visit Kawarayu Onsen, Yamakikan is the best ryokan in town for a taste of the traditional Japanese ambiance. On top of the wooden structure from a few centuries ago, Yamakikan is decorated with various old posters and town maps, giving you a clearer idea of how the onsen town used to look. In addition, Yamakikan has a private onsen tub and a library renovated from traditional storage!

Ⓒ 山木館

For more information, refer to our article on Yamakikan!

Yamba Ohashi Bridge (八ッ場大橋) and Bungy Japan Yamba Bungy (八ッ場バンジー)


Yamba Ohashi Bridge, completed in 2014, is one of the three bridges crossing the Agatsuma River as part of the Yamba Dam construction project. The bridge closest to Yamba Dam offers a panoramic view of the dam lake.

As it is between Fudoo Bridge and Yamba Dam, Yamba Ohashi Bridge is a great spot for a photo of Kawarayu Onsen‘s two popular tourist spots. A few monkeys might even cross the bridge when you get there (^_-)-☆.

If you are after some thrill, visit Bungy Japan Yamba Bungy, close to the Yamba Ohashi Bridge. After all setups are completed, you will jump off the bridge from 45 meters above the water!

For more information about bungy jump, refer to the official website HERE.

  • Yamba Ohashi Bridge is around a 20-minute walk from JR Kawarayu-Onsen Station.
  • If you plan to drive, there is a car park at the north end of Yamba Ohashi Bridge.

Yamba Dam and the Surrounding Attractions


Yamba Dam (八ッ場ダム) at the south end of the Agatsuma Gorge is undoubtedly the prominent landmark of Kawarayu Onsen. It can even be said that the construction of Yamba Dam made the hot spring town famous. So when planning your visit to the hot spring town, remember to allocate an hour or two to this scenic and spectacular spot!

For what to expect on the day, refer to our article on Yamba Dam and the Surrounding Attractions!

Mugi no Kaori (うどん専科 麦の香り)

If you don’t mind a non-vegetarian broth/dipping sauce, stop at Mugi no Kaori when you visit Yamba Dam. It is one of the most popular restaurants in Kawarayu Onsen. The restaurant has a welcoming and homey ambiance. Its reasonable pricing makes it a hidden gem in the hot spring town.

Sanuki udon is served at the restaurant, so the noodles are chewier than usual. Apparently, the owner was trained in restaurants in the northern Shikoku region where Sanuki udon originated. For a side dish, the crispy tempura is amazing! Combining the two, order a bowl of vegetable tempura udon (野菜天うどん)! But remember to let the staff know to remove the bonito flakes if you are a vegetarian/vegan.

Mugi no Kaori has a few different types of seating, including the Japanese-style low tables. When the weather is nice, the terrace seats are recommended. You might encounter other customers’ lovely dogs there too!

☛ Arriving before noon is recommended to avoid queueing up for a table. Especially on weekends and public holidays, Mugi no Kaori can be nearly full soon after it opens.
☛ Ordering a large serving is better for those who tend to eat a lot.

Mugi no Kaori’s Business Hours and Access Information

  • Mugi no Kaori is open from 11 am to 2:30 pm or until sold out from Thursday to Tuesday.
  • The restaurant is just a 5-minute walk from Yamba Dam.

Agatsuma Gorge (吾妻渓谷)

Ⓒ 群馬県観光物産国際協会

Agatsuma Gorge is a must-visit scenic spot in Kawarayu Onsen. The stunning gorge tucked away in the mountains of Gunma is a designed National Place of Scencry Beauty. Especially during the autumn leaves and fresh green seasons, the sheer valley is so beautiful when buried in red and green trees!

So refer to our Agatsuma Gorge article for what to expect on the day!

Yamba Tenmei Mudflow Museum (やんば天明泥流ミュージアム)

In 1783, Mt. Asama erupted. As a result, a massive mudflow buried and submerged the villages in Yamba. Taking the opportunity during the construction of the Yamba Dam, an excavation of the ruins site took place, and its findings are documented at the Yamba Tenmei Mudflow Museum. On the same site, there is a part of the former Naganohara Town Daiichi Elementary School building, one of the oldest wooden school buildings in Gunma Prefecture.

The 10-minute short film played at a theater close to Yamba Tenmei Mudflow Museum’s entrance, paints a good picture of the rural lifestyle at the time. It is also where you can feel how desperate the villagers must have been when they saw the mudflow coming their way. The explosion sound of the Mt. Asama eruption and the Tenmei mudflow are realistically reproduced. Apparently, people in Kyoto and Osaka could hear the explosion!

Tenmei (天明) is the era name at the time.

The film is played at 15 to 20-minute intervals.

Yamba Tenmeideiryu Museum’s Exhibition Areas

In the Teimei Mudflow Exhibition Room (天明泥流展示室), utensils, tools, and village models are on display. Although the explanation panels are in Japanese, most exhibits are also labeled in English, so it shouldn’t be hard to figure out what is in front of you.

Historical documentation and recording of the events are placed in the exhibition room. The drawings on these documents make it easy for us to understand the entire event, including the small eruptions to the event’s climax, when the volcano spews out large amounts of pumice, volcanic ash, pyroclastic flows, and lava flows.

There is even a ground-to-ceiling container filled with the dried mud layer after the mudflow. Its height indicates the mud layer that covered the 5 villages in the Yamba area. If the dried mud has a height of around 3 meters, it means the layer must be much thicker when water is contained. It is clear that nothing could survive without escaping. Parts of the crushed houses can also be found in the museum, telling you how powerful the mudflow was. While the villagers lost their homes, few people died.

What was discovered during the excavation isn’t limited to the ruins of the Yamba village. Items from the Jōmon period (14,000 to 300 BC) were also found.

Around 2,200 years ago, the technique of rice cultivation was brought to Japan. It was determined that this was when the Yamba settlements disappeared, probably because the weather wasn’t suitable for growing rice.

Yamba Tenmeideiryu Museum’s Opening Hours, Admission Fees, and Access Information

  • Yamba Tenmeideiryu Museum is open from 9 am to 4:30 pm from Thursday to Tuesday.
    • The last admission is at 4 pm.
    • If Wednesday is a public holiday, it will close on the next business day.
    • It is also close from the end of December to the beginning of January.
  • The admission fee is
    • 600 yen for adults
    • 400 yen for elementary and junior high school students
  • Yamba Tenmeideiryu Museum is a 4-minute drive or a 35-minute walk from JR Kawarayu-Onsen Station.

Yukake Festival (湯かけ祭り)

If you love to witness interesting festivals, visit Kawarayu Onsen in January. Before dawn on the 20th of January, young men in the town wearing only loincloths will gather in front of Ōyu. The festival, with more than 400 years of history, involves the young men splashing hot water on each other in the sub-zero coldness. It is said that good luck is brought to you when someone pours the hot spring over you!

As an onlooker, you might want to wear a raincoat because you might get wet too.

Exploring Other Amazing Destinations Close to Kawarayu Onsen

Click the photo for more great destinations near Kawarayu Onsen!

Kawarayu Onsen is surely a hidden gem for everyone to enjoy Japan’s rural area. But you might be interested in visiting a couple more amazing sightseeing destinations near Kawarayu Onsen. For example, Kusatsu Onsen in the photo is a place in Gunma Prefecture that should not be skipped!

So refer to our Recommended Destinations Around Kusatsu Onsen for information about what Gunma Prefecture can offer!