Kusatsu Onsen | One of Japan’s Best Hot Spring Towns

Kusatsu hot spring water flows out of the yubatake (hot water field) high above sea level

Nestled 1,200 meters above sea level in the mountains of Gunma Prefecture, the rustic town of Kusatsu Onsen is a hidden gem that goes unnoticed by many visitors to Japan. Considered to be a top hot spring in Japan, its location away from any major train lines has kept it from becoming popular with international tourists. That said, if you’re looking to experience a traditional Japanese onsen town, I can think of no better choice than a visit to Kusatsu Onsen.

As an onsen town, the health benefits of Kusatsu Onsen’s waters are legendary. A soak in the sulfuric waters is said to have the potency to cure any and all ills save for a broken heart. Furthermore, in the late 1800’s German doctor Erwin von Baelz even recognized the rejuvenative powers of Kutasu. It is said that the hot springs of Kusatsu Onsen are so acidic that they can dissolve a 6-inch nail in under ten days; hence, you can imagine the survival rate of harmful bacteria.

Kusatsu Onsen’s hot springs are extremely sulfuric give the town and its ski resort its green surroundings

Each minute more than 32,000 liters of heated spring water gush from their source at Mt. Shirane, a still-active volcano. To put that number in perspective, imagine 230,000 barrels full of hot spring water! The sheer volume of the flow allows for the large number of facilities in Kusatsu Onsen and the city claims to have one of the most plentiful springs in Japan. Unlike other areas, the waters of Kusatsu Onsen are never diluted, reheated, or otherwise adjusted which only serves to bolster their impressive healing capabilities.

Compared with other popular onsen towns, Kusatsu Onsen is a bit of a hassle to get to but the rustic vibe of the area, coupled with its impressive scenery, make the journey worth it. Given its remote location, getting to and around Kusatsu Onsen can be intimidating even for long term residents but fret not; in this guide I have included any and all information you might need to get the most out of your stay!

Note: If you’ve never been in one before, check out my ultimate onsen guide first before going to Kusatsu!

How to Get There

Direct buses leave from this train station for the Kusatsu hot spring resort via the Kusatsu Bus Terminal

As I alluded to previously, getting to Kusatsu Onsen from Tokyo is a bit of a challenge. Due to the hot spring town’s remote location in the mountains of Gunma, no trains are able to service the town directly. Instead, you’ll need to take a local bus from Naganohara-Kusatsuguchi Station if you’re coming via public transportation.

That said, those who have an international driver’s license will find that renting a car for the journey is a far better solution. Just be weary of the snow during winter as it can pile up to several meters high. If a storm rolls in then you might end up extending your stay; not that there aren’t worse places to be stuck. If you’re worried about driving, consider Ikaho Onsen instead.

Those who will be coming by train will find the limited express trains departing from Ueno to be the fastest means of transportation. There are only a handful of trains per day though so you’ll need to be weary of time schedules, especially on the way back. Be sure to consult Jorudan or a similar service prior to your day of departure.

Once arriving in Naganohara-Kusatsuguchi you’ll need to make your way to one of several buses that will take you to Kusatsu Onsen itself. The buses are pretty hard to miss and there should be a number of them lined up outside of the station. As of this writing, the fees are 700 yen which is to be paid upon exiting at the Kusatsu Onsen Bus Terminal.

If the trains seem too much of a challenge, I’ve also read there are multiple buses that depart from Shinjuku for the Kusatsu Onsen Bus Terminal. Though slower than the limited express trains, these buses are much more affordable (about 2,000 yen less in total). Unfortunately, I have personally never taken the bus to Kusatsu Onsen so I cannot comment on their level of comfort.

The Yubatake’s Hot Spring Water

The hot water in Kusatsu Onsen’s Yubatake is the source of the hot springs baths and has the largest volume in Japan

Central to the area of Kusatsu Onsen is what is known as the yubatake (meaning “hot water field” in Japanese). Its location at the heart of the onsen town means that it will serve as a major landmark to which you can return while exploring Kusatsu Onsen. Indeed much of the city’s navigational aids are designed to directly reference the yubatake.

At the yubatake, hot spring water gushes from its volcanic origins down thick pinewood channels where it is cooled to a tolerable temperature. These pathways contain copious amounts of resin which allow them to withstand the strong acidity of the hot spring waters.

Many nearby ryokan inns also employ similar types of wooden materials in the construction of their baths. Because of this, the Kusatsu Onsen boasts a rustic atmosphere that most modern towns lack. At times, it almost feels as if the hot spring town’s imagery was ripped directly from the scene of Hayao Miyazaki’s Spirited Away.

Thanks to the nearby active volcano, Kusatsu is more than a small onsen town and is one of the best in Japan

As the yubatake is a major source of hot spring water for Kusatsu Onsen, the majority of the major onsen and ryokan inns are unsurprisingly clustered around it. Alone, the yubatake is responsible for as much as 4,000 liters of hot spring water per minute. The high water output is known to give rise to entrancing clouds of steam which are especially stunning during the colder months.

Many people have noted that the high amounts of sulfur produce an egg-like smell. While rather unpleasant at first, I found that within a minute the nose becomes accustomed to the scent. If you can bear the initial few seconds, the stench should fade into the background momentarily.

Since the Edo period, performers in used large wooden paddles made for hot water to stir thermal water

Directly adjacent to the yubatake you’ll find the new Netsu-no-Yu building which was recently rebuilt in 2015. Here visitors can see a traditional Yumomi performance which is a traditional means of cooling down hot spring water to bathing temperatures. Performers use wooden paddles to churn the water in a way that expedites the cooling process while chanting traditional folk songs. Yumomi performances are held six times per day in Kusatsu Onsen and are priced at 600 yen per adult. From what I could gather there are extremely long lines so this might be something that you consider skipping.

Note that there are many restaurants around the yubatake and the Netsu-no-Yu building in Kusatsu Onsen. At the very least, I suggest you get an onsen manju if you’ve come all the way up here from Tokyo. It’s a cool way to experience a bit more of local Kusatsu Onsen culture after enjoying a yumomi performance.

How to Pick Your Hot Spring

An public bath near the Netsunoyu Building and the hot water field in town centre (Kusatsu machi)

When it comes to selecting an onsen, you’ll be spoiled for choice in Kusatsu Onsen. There are more than a dozen small community baths which can be used freely by both locals and tourists scattered across the town. Nevertheless, the small size, coupled with the lack of English language instruction, make these rather hard to find. Instead, I suggest looking at one of three main public facilities. Although they cost a little bit more you’ll not have to worry about fitting into a tiny bath with other residents.

Likely you’ll end up picking from one of the following hot spring baths…

  • Goza-no-Yu
    Admission: 500 yen
    Hours: 7 AM to 9 PM
    Location: 1–2 minutes from the yubatake
    This relatively new onsen opened in 2013 and houses both a stone and wooden bath which are alternated among the genders. Each of the baths also consists of two different pools that are fed by different thermal vents.
  • Otaki-no-Yu
    Admission: 800 yen
    Hours: 9 AM to 9 PM
    Location: 15 minutes from the yubatake
    This public bath house is built with a traditional interior that houses multiple wooden tubs of varying temperatures ranging from bearable to extremely hot, a practice known as “awaseyu” in Japanese.
  • Sai-no-Kawara Rotenburo
    Location: 10 minutes from the yubatake
    Hours: 9 AM to 8 PM
    Admission: 600 yen

My favorite of the three, this large open-air bath is one of the biggest in Japan. We’ll cover this more in depth in the next section. While you can enjoy the water quality of Kusatsu Onsen anywhere in the town, this is my favorite during winter as you can cool off in the snow. Honestly, while hot springs are great year round, a winter onsen soak is one of the best experience you can have in Japan.

By the way, visitors staying in ryokans will almost certainly have an onsen built into their facility that they can use free of charge. In addition, there are also several foot baths called ashiyu which can be used free of charge by tourists. One of these is located directly next to the yubatake and another near the Kusatsu Onsen Bus Terminal.

Kusatsu Onsen’s Sai-no-Kawara Park

SaiNoKawara Park looks like it has many outdoor hot spring baths but many hot springs aren’t suitable to go in

Near the bottom end of the yubatake you’ll find several streets branching out to the west. These all converge into Sai-no-Kawara Street which contains a lively little shopping lane extending from the yubatake to Sai-no-Kawara Park. Along the streets you’ll find numerous ryokan that have been welcoming guests for hundreds of years. While strolling this cozy street you’ll also encounter many charming shops where you can buy any number of traditional sweets and goodies.

If you continue west on this street for approximately 10 minutes, you’ll happen upon the bubbling expanse of hot spring lagoons. In this spacious area, numerous wells spring forth from the ground and coalesce to form steaming rivers of piping hot water. Remember to be careful so you don’t end up in a scalding pond of sulfuric water when trying to get a picture of the eerie steam rising from the waters! Sai-no-Kawara has absolutely no guard rails or anything of the sort.

This small town inari shrine in Agatsuma-gun is outside inside SaiNoKawara Park

Shortly after entering the park you’ll come across a small Inari shrine with the multiple torii gates in the style of the parent shrine in Kyoto. Though in summer months reaching the actual shrine might be easy, as you can see in the picture above, winter is an entirely different story. Don’t be an idiot like me. The mountains of Gunma are the last place you want to end up with a broken leg while visiting Japan.

SaiNoKawara Open Air Bath in SaiNoKawara Park is one of the best in Japan

Though the park grounds are quite nice by themselves, the big attraction is the aforementioned rotenburo or “open-air hot spring bath.” Located toward the latter half of the park, the Sai-no-Kawara Rotenburo is a communal bathing facility where you can enjoy the crisp mountain air while soaking your body in Kusatsu Onsen rejuvenating spring water. Of all the three famous onsen in Kusatsu Onsen, this one is by far my favorite as it enables being outdoors while bathing.

A stone tablet in Japan tells the tale of Sainokawara Park

While in the park, please heed this old wives tale of warning. In an age long ago, this park of Japan was once called the “Demon’s Spring.” Legends tell of a demon who once lived in these parts and as such, visitors should not speak loudly else he reappear. The park’s original name came from the bubbling noise of the springs which emit sounds similar to a kettle. The locals say that when one would approach, the noise would suddenly cease and this strange phenomenon was supposedly attributed to the demon who lived here.

More than One of Japan’s Best Hot Springs

The torii of Kusatsu Shirane Shrine can be found near Sainokawara Park. It honor’s Kusatsu’s hot spring water

Kusatsu Onsen is first and foremost a hot spring town and the baths are its main attractions. Though the area is blessed with beautiful natural mountains, hiking and skiing are only a small part of the Kusatsu Onsen allure (that said, do check out Kusatsu Onsen Ski resort). Likewise, the area is not really home to any famous shrines or temples like Kyoto or Kamakura. Nevertheless, if you’re in the mood to see some spiritual spots before or after your dip in the onsen, then the following two options are worth a quick visit.

  • Shirane Shrine
    Mt. Shirane is the source of the hot spring waters and this shrine is dedicated to the god Yamato Takeru. According to local myth, this deity was responsible for the initial discovery of the area’s hot springs. The shrine can be reached via a set of steep stone stairs that are located a few minutes away from the yubatake.
  • Kosen-ji
    This Buddhist temple is located only a few seconds away from the yubatake behind Goza-no-Yu. Like Shirane Shrine, this too is located atop a long staircase. The temple offers a wonderful view of the yubatake. If you’re visiting during winter I found the area to be especially beautiful when covered in snow but it’s not something that I’d consider a must see.
In addition to Kusatsu Onsen Ski Resort, this town also has a lot of other options for fun

Another hidden gem that I found while exploring the quaint streets of this hot spring town was the retro game center pictured above. If you want to take a trip back to the days of entertainment before the digital age, I suggest quick visit to this peculiar spot. There are all sorts of game consoles to enjoy and an experience like this definitely can’t be had back in Tokyo!

What about Kusatsu Nightlife?

Those not staying at Kusatsu Ski Resort should explore the popular tourist destination at night

While not exactly falling under the category of nightlife, one thing that I implore you to check out at night is the yubatake. The whole area is lit up in a way that causes a stunning array of colors to appear from the mist. If you’re looking to take some pictures of your journey, I cannot more highly recommend a shot of the yubatake at dusk like picture above.

That said, like most countryside towns, Kusatsu Onsen doesn’t have the bustling nightlife that major metropolitan areas have. Most of the people coming to the area are staying at ryokan with either their significant other or with family. What this means is that there are limited options to party at night.

Unlike in Tokyo, there are only a few restaurants in Kusatsu for those not staying at Kusatsu Ski Resort on Mount Shirane

I’ve taken the guesswork out of finding a decent place for a drink so please check out any of the following…

  • Daitokan Lobby
    On the second floor of this ryoka there is an arcade game center with a collection of machines as well as several dart boards. There’s a small bar here as well where you can grab a drink before enjoying some games. If you do decide to swing by here, tell the bartender Masaru that Donny sent you!
  • Cafe Bar R
    I ended up having a lot of adventures here drinking with locals so I wanted to introduce it. There’s nothing really special about this place other than it’s one of the only place in town I could find that was open relatively late. If you’re looking to drink until the wee hours of the morning, I highly suggest it.
  • Karaoke in Kusatsu
    There are several places offering Karaoke in the area but seeing as I visited the place alone, I cannot vet their quality. If you’re in a group though this might be a fun option. Japanese karaoke is different than in the west so keep that in mind (more here if you’re curious).
  • Kusatsu Snacks
    If you take a side street from Sai-no-Kawara Dori you’ll find a collection of snack bars or overpriced watering holes that will seat a pretty girl with you while you drink. If you’re really on a bender with the boys this could be fun otherwise I suggest skipping it while in Kusatsu

Kusatsu Onsen Accommodations

A ryokan stay with private baths atop Mount Shirane is a welcome escape and some even pick you up from the train station

Like the majority of local in Japan, most visitors to Kusatsu Onsen are going to stay at a traditional ryokan. It’s hard to beat one of these when it comes to the “full package” experience of a Japanese hot spring town (especially ones with private onsens). This is especially true if you don’t have one booked at some point during the rest of your stay in Japan. The Japanese breakfast alone is worth the experience.

Given that many hotels and ryokan in Kusatsu Onsen have no English capabilities, you’re going to need to go through a middleman unless you’re already using Japanese in daily life. I found JAPANiCAN to be one of the easiest to use when looking for a ryokan in Kusatsu Onsen. You’ll likely be limited for choice unless you book far in advance so please keep that in mind.

The best part about staying in a ryokan is experiencing Japan’s traditional hospitality and having accesses to an onsen built into the facility. That said, if you’d rather save some money and plan on using the public onsen listed above, I highly recommend staying in an Airbnb as this is what I did when visiting and I have no regrets about it.

Regardless of what you do, this Kusatsu Onsen is an overnight destination so plan accordingly. Unlike with nearby Ikaho Onsen on Mt. Haruna, the transportation schedules from the train station just do not allow for this remote hot spring town to be done as a day trip. Despite this, I cannot think of a more relaxing and rejuvenating way to spend a day and a half away from Tokyo in Japan!

Until next time travelers…

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Donny Kimball
Donny Kimball

I'm a travel writer and freelance digital marketer who blogs about the sides of Japan that you can't find in the mainstream media.

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