Vegetarian's Japan Guide

Manza Onsen: The Hot Spring Town Closest to the Sky in Japan

While the most famous hot spring resort in Gunma Prefecture is Kusatsu Onsen, Manza Onsen (万座温泉) on its west is the destination for all nature lovers! Situated at an elevation of 1,800 meters, Manza Onsen is the hot spring town closest to the sky in Japan! Although located in a mountainous area, most of the ryokans in the town are surprisingly large and splendid, and most of those ryokans have at least one outdoor hot spring pool!

Besides being a renowned winter skiing destination, Manza Onsen is the perfect summer resort in the Kanto region. Even in the middle of summer, the temperature drops to 15 degrees at night. Compared to Kusatsu Onsen, the ryokans/hotels here offer accommodation plans with higher CP value. Plus, many of them have hot spring pools with magnificent views!

As a summer resort, the average temperature at Manza Onsen is still over 10 degrees lower than in Tokyo. So bring enough clothing!

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How to Get to Manza Onsen

  • From JR Ueno Station (上野駅), take the limited express, Kusatsu (特急草津号) and get off at Naganohara-Kusatsuguchi Station (長野原草津口駅). From there, change to JR Agatsuma Line (吾妻線) and get off at JR Manza-Kazawaguchi Station (万座・鹿沢口駅).
    • You can also take a bullet train to JR Takasaki Station (高崎駅) and change to JR Agatsuma Line.
    • Refer to HERE for the timetable for this leg of the journey.
  • From Manza-Kazawaguchi Station, take a local bus and get off at the terminal stop, Manza Onsen (万座温泉).
    • The bus trip takes about 40 minutes.
    • Refer to HERE to search the bus service’s timetable.
  • Bus services also depart from Karuizawa.
    • If you read Japanese, you can refer to HERE for an overall service timetable.
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Manza Onsen Nisshinkan (万座温泉 日進舘) has an accommodation plan that includes an express bus service from Shinjuku.
Manza Onsen Nisshikan, Manza Prince Hotel, and Manza Kogen Hotel provide free shuttle bus services to and from Karuizawa.

Manza Onsen’s Brief Profile

Manza Onsen has around 18 hot spring sources. Most of them are acidic sulfur springs. In fact, one of them has the highest sulfur concentration in Japan. But don’t worry! The onsen in the hot spring facilities is treated so that the acidity is suitable for bathing. The onsen at Manza Onsen comprises more than 20 spring qualities.

In the past, many who suffered from respiratory, gastrointestinal, skin disease, and rheumatism would visit Manza Onsen for medical spa treatments. There are many stories about how the hot springs cured intractable diseases. In addition, Manza Onsen’s hot spring is known to be good for your skin, so it is no surprise that the hot spring resort is popular among women!

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If you are concerned that the hot spring at the ryokan isn’t fresh, that won’t be the case in Manza Onsen. The hot spring town has around 5,400,000 liters of onsen flowing out of the spring sources each day. In other words, Manza Onsen has fresh hot springs that can fill around 20 25-meter swimming pools daily!

Most of the hot spring at Manza Onsen is cloudy. If you are after something special, visit Manza Kogen Hotel (万座高原ホテル). It has an outdoor hot spring pool, where the color of the onsen looks yellow.

Besides hot springs, Manza Onsen is also the destination to admire the alpine plants. From May to August, various gorgeous flowers such as Yamatsutsuji (a type of Rhododendron) and thistle bloom across the hill. In autumn, the colorful fall foliage scenery enchants those who visit the hot spring town.

Manza Nature Center (万座しぜん情報館)

Manza Nature Center at Manza Bus Terminal (万座温泉バスターミナル) is the hot spring town’s tourist center. In addition to the tourist information desk, exhibits of volcanoes, geography, hot springs, alpine plants, and creatures living in the surrounding area can also be found there. There are also animal furs at Manza Nature Center. Most of them come from road kills.

As the area is the habitat for bears, check with the staff at Manza Nature Center for any bears recently sighted in the area for your safety. The staff will also let you know what alpine plants can be seen on the day and where to find them.

The good thing about the center (opened in 2018) is that it has English notation for the permanent exhibits, making it easier for foreigners to understand the nature and the history of the Manza Onsen and Kusatsu area. So feel free to stop by to gather information before trekking those trails or if you want to take a break around the hearth after enjoying the hot springs.

If you need a toilet break, the facility at Manza Onsen Tourist Center is clean.

Moreover, Manza Nature Center also holds tours into Manza Onsen’s nature. But the tours are only available in Japanese.

From the lookout at the back to the nature center, you can get a clear view of Karabuki, one of Manza Onsen’s famous natural spots.

Tip: You can purchase Manza Onsen’s hot spring pass, Manza Onsen Yumeguri Tegata (万座温泉湯めぐり手形), from the center.

Manza Nature Center’s Opening Hours and Access Information

  • Manza Nature Center is open from 9 am to 4 pm.
  • It is very close to Manza Bus Terminal.

Manza Karabuki (万座空吹)

The first tourist spot you can visit is Manza Karabuki, as it is located just next to the bus terminal.

Karabuki was a crater. The steam rising from the rocky area was the underground water and the rainwater seeped into the ground. Because sounds were made when the steam was emitted, it was named Karabuki.

Note that it is silently releasing the smelly steam now, and the steam doesn’t come out continuously either.

As the poisonous hydrogen sulfide gas also comes out together, it is safer to overlook it from the observation deck at the back of Manza Nature Onsen Tourist Center (万座しぜん情報館 展望テラス). Due to the volcanic gas, the area is covered by rough rock surfaces, as no other lifeforms can grow in the harsh conditions. The steam is also why Manza Onsen’s air smells of sulfur.


You can also check with the staff to see if the road to Manza Karabuki Observation Deck has re-opened. Following the direction sign and climbing up the stairs, the observation deck offers an even better view of Manza Karabuki!

Tip: If you want to adore Manza Karabuki while bathing, visit Manza Prince Hotel‘s Komakusa no Yu (こまくさの湯). Manza Karabuki is just in front of the outdoor onsen pool! The other hotel where you can get a good view of Manza Karabuki is Manza Hotel Juraku (万座ホテルジュラク).

Manza Onsen Ski Resort (万座温泉スキー場)

In winter, Manza Onsen Ski Resort is where most tourists gather during the day. While the resort is compact, it has enough width. Plus the snow quality at Manza Onsen is so high that the town has a nickname, Powder Snow Manza (粉雪の万座)!

Although Manza Onsen isn’t easy to get to, it almost always means no queue for the lifts! When the temperature rises in March, Manza Onsen usually still has nice powder snow, even if most ski resorts in the Kantō region have ended their snow season.

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Skiing at Manza Onsen Ski Resort

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The resort has an elevation difference of about 400 meters, providing a maximum skiing distance of about 2 kilometers. The slopes have a maximum slope degree of 30 degrees. They consist of 14 courses suitable for skiers and snowboarders of different experience levels. So if you are in the area during winter, how about enjoying the powder snow at Manza Onsen Ski Resort?

If you are a beginner, it is best to take a lesson at their skiing school first. The slope for the beginner courses here is still steep.

If you are staying at Manza Prince Hotel, you can start skiing as soon as you step out of the hotel. The Prince Slope is located next to the best hotel in Manza Onsen. At the top of the Prince Slope is the Manzayama Slope, extending to Mt. Manza’s summit (万座山).

Same as other ski resorts around the world, ski/snowboarding gear for adults and children can be rented from Manza Onsen Ski Resort, so coming empty-handed wouldn’t be a problem! You can refer to the price table HERE to budget your trip.

☛ It is free for children up to 12 years old to use the lift!
☛ If you like animals, ski down the Animal Forest Trail (動物の森). You are likely to spot different animals hiding in the forest!
☛ The resort’s lift also operates during the fall foliage season in October, so your autumn foliage adoration session at Ushiike Pond can be extended by taking the lift up to the summit for even more spectacular views!

Ushiike Pond (牛池)

Ushiike is the only pond in Manza Onsen. It didn’t get its name because it looked like a cow but because of the pond’s depth. While it might seem like a shallow pond, Ushiike has a depth of 3 meters. So if a cow walks in, the pond has enough depth to sink it.

The water there has a relatively strong acidity. It has a high transparency that you can almost see the bottom. Reflecting the surrounding nature, it is one of the most scenic spots in Manza Onsen. Because it offers a completely different natural view than the spots closer to Manza Yubatake, how about visiting Ushiike as a morning walk before breakfast?

The pond has a circumference of around 200 meters. Following the promenade around the pond, you can enjoy a relaxing 20-minute stroll. In autumn, the vivid fall foliage will make this part of the town somehow mysterious.

☛ It is best to bring a bear bell when you visit Ushiike Pond. If you don’t have one, there is one along the promenade. Ring it to alert the bears nearby to stay away.
☛ There is a small pavilion at Ushiike, a great spot for a picnic!

Manza Yubatake (万座湯畑)


Yubatake means a hot spring field. The Yubatake in Kusatsu Onsen is the most famous in Japan, but other hot spring resorts in Japan also have their Yubatake.

Manza Onsen’s Yubatake has a completely different vibe compared to the one in Kusatsu. The greenish milky source has a temperature of 80 degrees and is the biggest spring source in the town. Like Kusatsu Onsen, Manza Yubatake was built to cool down the hot spring, allowing us users to enjoy it at a ryokan.

Although you can’t get close to Yubatake as it emits hydrogen sulfide gas, the Yubatake can be seen clearly from the promenade.

To get to Manza Yubatake, go down the slope at the back of Nisshinkan‘s entrance.

Manza Shakushidō (万座薬師堂)

Manza Shakushidō located halfway up Mt. Kumashirō was established in 1715 and restored in 1924. It is a guardian temple of Manza Onsen. If the temple’s doors are closed, feel free to open them to worship the Buddha. As it is at the trailhead of Kumashirō Natura Trail, even if you are an atheist, it won’t hurt to greet or bow down to the Healing Buddha enshrined here and pray for a safe and happy visit to Manza Onsen.

If you plan to visit the hot spring resort on New Year’s Eve, check with the tourist association if the countdown event is on for the year. Stepping into the new year at an altitude of 1,800 meters with numerous lit candles surrounding you will definitely make the year’s New Year’s Eve unforgettable!

There might even be Amazake (a traditional sweet, low-alcohol or non-alcoholic Japanese drink made from fermented rice) or other alcohol available to keep you warm!

Kumashirō Nature Trail (熊四郎山の遊歩道)

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Kumashirō Nature Trail is where you can experience the power of an active volcano at Manza Onsen. It is sometimes referred to as Manza Pilgrimage Course (万座お参りコース) as the trail passes through Inadunagū Shrine.

The promenade in Mt. Kumashirō can be accessed from Nissinkan (日進館). Hiking up from Nissinkan, you will first reach Manza Shakushidō (万座薬師堂), a temple enshrining the Healing Buddha. Further up from Manza Shakushidō is a shrine in a cave called Kumashirō Cave (熊四郎洞窟).

Soon after crossing the bridge over the Manza River (万座川), the hiking trail leading to Manza Onsen Observatory (万座温泉展望台) offers a panoramic view of the town, including Yubatake and the installed pipes to source the onsen from various hot spring sources. Your visit to Manza Onsen will be more memorable after knowing how the hot spring is drawn and transported to the onsen pools!

☛ A return trip to Manz Onsen Observatory takes around 60 minutes.
☛ It is best to carry a bear bell with you when trekking through the trail. If you don’t have one, check with your hotel’s concierge. They might have one that you can rent.

Manza River flowing from Mt. Kusatsu-Shirane (草津白根山) has a strong acidity with a pH value of 2 to 3. You won’t be seeing fish swimming in the river.

If you choose to go straight instead of crossing the bridge, you will reach another observatory called Kumashirō Observation Deck (熊四郎山展望台), which offers a panoramic view of Manza Onsen from a different angle.

Note that the promenade is inaccessible in winter due to heavy snowfall. Also, please do not enter areas restricted (guarded by ropes) as there is a high concentration of hydrogen sulfide gas beyond the ropes.


Kumashirō Cave (熊四郎洞窟)

A faded vermilion wooden torii gate marks Kumashirō Cave. The small shrine in the cave is Inadunagū (稲網宮). There are two theories as to why the cave was named Kumashirō. The most realistic one is because Manza Onsen’s spring source was discovered by a hunter called Kumashirō. The mountain around the spring source was thus called Kumashirō.

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A sadder theory is about a hunter and his two dogs who spent a night in the cave.

In the middle of the night, the dogs started barking and barked even louder after the hunter asked them to stop. This angered the hunter as he was unable to sleep. He pulled out his machete and cut off the dogs’ heads. Surprisingly, the dogs’ heads flew into the sky. As he looked up, he realized why they wouldn’t stop barking. There was a gigantic serpent above him, and it was going to attack him in the next second. Luckily, the dogs’ heads bit the serpent’s neck, and the serpent died soon after.

Realizing his mistake, he named the cave after his dogs, hoping to console their souls. This is why the cave was named Kumashirō, after his loyal dogs, Kuma and Shiro.

The rock that forms the cave is Trachte. Due to the erosion of the acidic water, the cave was formed naturally. Because Yayoi-style earthenware was discovered from the cave, it was determined that the site was a prehistoric dwelling.

From Manza Yubatake, it takes around 10 minutes to Kumashirō Cave. You can follow the trail and continue hiking up to the summit.

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Although Manza Onsen has no public bathhouses, most accommodations accept day visitors. This means you can hop between each ryokan/hotel during the day to bathe in various hot spring pools with different scenery. Also, remember to have another onsen session at night if the weather is good. Instead of the mountainous views, you will have a sky filled with stars to adore!

For more information about our recommended ryokans and hotels, refer to our Guide to Ryokans and Hotels in Manza Onsen.

Events and Festivals at Manza Onsen


Dicentra peregrina is an alpine plant that blooms each year at Manza Onsen in July. Because of the plant’s cute flower, it is also known as the Queen of Alpine Plant in Japan.

The plants nearly disappeared from Manza Onsen as many of them were dug out illegally at one point. Thanks to the effort of the locals, we can still meet a field of these gorgeous plants when we visit the hot spring town.

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The festival, usually held in mid-July, is an event for dicentra peregrina. On the day, lottery draws, free hot spring sessions, Taiko performances, and much more are held in Manza Onsen. If the event is on when you visit the hot spring resort, join the locals and get a taste of how the Japanese celebrate!

Discover Attractions in Kusatsu Onsen

Click the photo for more information about Kusatsu Onsen’s attractions!

If you haven’t already, plan a visit to Kusatsu Onsen, one of Japan’s most well-known hot spring towns!

In addition to the public and communal bathhouses, Kusatsu Onsen has a lot to offer. Whether it is soba noodles, traditional sweets or outdoor activities such as obstacle courses and skiing, it is almost impossible to be bored at Kusatsu Onsen!

For more information, refer to our article on Kusatsu Onsen (=゚ω゚)ノ.

Exploring Other Amazing Destinations Close to Kawarayu Onsen

Manza 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 Manza 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!

Click the photo for more great destinations near Kawarayu Onsen!