Gunma Onsen Guide: Kusatsu, Takaragawa, Manza & Hoshi — Which Hot Spring Is Right for You?

Why Gunma Is Japan's Onsen Capital

Gunma Prefecture, about two hours north of Tokyo by Shinkansen, has 453 natural hot spring sources and over 100 onsen towns — more than almost any other prefecture in Japan. According to Visit Gunma, Gunma's hot spring heritage draws from the volcanic geology of the Joshinetsu highlands, producing waters that range from strongly acidic at Kusatsu to sulfurous at Manza to naturally heated mineral springs at Hoshi Onsen.

What makes Gunma stand out is not just volume but variety. Within a three-hour radius from Tokyo Station, you can choose between a lively onsen town with public bathhouses and restaurants, a secluded riverside outdoor bath in a mountain gorge, Japan's highest-elevation sulfur springs, or a Meiji-era bathhouse designated as a National Tangible Cultural Property. Most travelers visiting Gunma's hot springs will find that the hardest part is choosing which one.

Gunma Onsen Comparison: Which Hot Spring Suits You?

At a Glance: Comparison Table

Onsen	Style	Elevation	From Tokyo	Day-Use Price	Key Feature	Atmosphere
Kusatsu	Hot spring town	~1,200m	~2.5h	~¥700 (~$5)	Yubatake (湯畑) hot water field	Lively, walkable, social
Takaragawa	Riverside rotenburo	~800m	~2.5h	¥1,000 (~$7)	Massive outdoor baths along river	Secluded, natural, rustic
Manza	Highland sulfur springs	~1,800m	~3h	¥800 (~$5)	Japan's highest onsen town	Remote, therapeutic, quiet
Hoshi Onsen	Historic ryokan	~700m	~3h	Guests only	Spring water rises through bath floor	Intimate, historic, exclusive

Choosing by Travel Style

First-time onsen visitor? Start with Kusatsu. It has the most infrastructure, English signage, and a walkable town center that eases you into the experience without requiring a car or advance planning.

Seeking nature immersion? Takaragawa's enormous riverside outdoor baths (露天風呂, rotenburo) surrounded by forest and mountains deliver one of Japan's most dramatic bathing settings.

Want healing waters at extreme altitude? Manza Onsen sits at approximately 1,800m on the flanks of Mount Kusatsu-Shirane, with sulfurous waters (硫黄泉) traditionally valued for skin and respiratory conditions.

Looking for a historic, once-in-a-lifetime experience? Hoshi Onsen Chojukan (長寿館) is an overnight-only Meiji-era ryokan where natural spring water rises directly through the wooden bath floor — a National Tangible Cultural Property with 1,200 years of history.

Kusatsu Onsen: Japan's Most Famous Hot Spring Town

Kusatsu Onsen (草津温泉) is one of Japan's top three hot springs and Gunma's most visited onsen destination. The town centers on the yubatake (湯畑) — a dramatic open-air hot water field in the middle of town where steaming spring water flows through wooden channels to cool before being piped to bathhouses. According to ONSENISTA, Kusatsu's sources produce approximately 32,000 liters of spring water per minute.

Kusatsu's waters are notably acidic, which is part of their reputation. The traditional yumomi (湯もみ) performance — where attendants stir the scalding water with large wooden paddles while singing — is a Kusatsu-specific custom worth seeing.

Public bathhouses like Shirohata no Yu open from around 6:00 AM to 10:00 PM, with day-use admission around ¥700 (~$5) for adults. No reservation is needed. The town is walkable with restaurants, souvenir shops, and multiple bathing options within a short distance of the yubatake.

For a detailed look at Kusatsu's bathing culture and history, see our Kusatsu onsen overview. For walking routes and dining, see our Kusatsu town travel guide. For Kusatsu's place in Gunma's broader onsen landscape, see Kusatsu Onsen in Gunma Prefecture.

Takaragawa Onsen: Massive Riverside Outdoor Baths

Takaragawa Onsen sits in the mountains of the Minakami area, near the headwaters of the Tone River. It is famous for its enormous riverside rotenburo — open-air baths built directly alongside the river, surrounded by forest. According to ONSENISTA, the site has also served as a film location due to its dramatic natural setting.

The main baths are mixed-gender (混浴, konyoku). Nudity is required — swimwear is not permitted. Some women-only sections are available. Many visitors on TripAdvisor note that mixed bathing is communal and non-sexual, but first-time visitors should be aware of the arrangement before arriving.

Day-use bathing costs ¥1,000 (~$7) for adults and ¥500 (~$3.50) for children. Hours are 6:00 AM to 10:00 PM. Overnight guests bathe for free. The facility closes on the 2nd and 4th Thursdays outside winter season.

For the full Takaragawa experience including riverside bath details and seasonal highlights, see our Takaragawa Onsen Minakami guide.

Manza Onsen: Japan's Highest Hot Spring Town

Manza Onsen sits at approximately 1,800m elevation on the slopes below Mount Kusatsu-Shirane, making it one of Japan's highest-altitude onsen areas. The springs are characterized by strong sulfurous waters (硫黄泉) — milky white with a distinctive smell — traditionally valued for skin conditions and respiratory health.

The altitude means weather changes rapidly even in summer, so pack layers regardless of season. In winter, Manza doubles as a small ski area, and snow-viewing baths are a highlight. However, winter access requires chains or winter tires due to mountain road conditions.

Public bathhouse day-use is around ¥800 (~$5) for adults, open 10:00 AM to 9:00 PM. Manza is the most remote of Gunma's main onsen areas — about 30 minutes by car from Kusatsu — and public bus service is limited, especially outside peak season.

For a detailed guide to Manza's highland retreat experience including accommodation and skiing, see our Manza Onsen highland retreat guide.

Hoshi Onsen Chojukan: Bathing in a Meiji-Era Cultural Property

Hoshi Onsen Chojukan (星野温泉 長寿館) is a ryokan with 1,200 years of history, housed in a building designated as a National Tangible Cultural Property. The defining feature is the main bathhouse: natural hot spring water rises directly through the wooden floor of the bath itself, creating a uniquely gentle and immersive experience.

The main bath is mixed-gender (konyoku). Hoshi Onsen is accommodation-only — there is no day-use option. Rates start at approximately ¥15,000 (~$100) per person per night including dinner and breakfast. Reservation is required.

The location is remote, in the mountains of the Minakami area, accessed via narrow mountain roads. This is a place for travelers seeking a quiet, deeply traditional experience rather than a convenient day trip.

For the full Chojukan experience including room types and what to expect, see our Hoshi Onsen Chojukan experience guide.

Getting to Gunma's Onsen from Tokyo

Kusatsu: Shinkansen + Bus from Tokyo Station

From Tokyo Station, take the Hokuriku or Joetsu Shinkansen to Takasaki, transfer to the JR Agatsuma Line to Naganohara-Kusatsuguchi Station, then a bus for approximately 60 minutes to Kusatsu. Total travel time is roughly 2.5 hours.

Takaragawa and Hoshi: Joetsu Shinkansen via Jomo-Kogen

Both Takaragawa and Hoshi Onsen are accessed from the Joetsu Shinkansen. For Takaragawa, ride to Jomo-Kogen Station and take a bus approximately 40 minutes to the onsen. Total from Tokyo: approximately 2.5 hours. For Hoshi Onsen, the route is similar via Minakami Station, with a bus taking approximately 1 hour. Total from Tokyo: approximately 3 hours.

Manza: Via Kusatsu or Direct Bus

Manza is most easily reached as an extension from Kusatsu — about 30 minutes by car via Route 292. Direct public bus options from Tokyo exist but are infrequent. Total travel time from Tokyo is approximately 3 hours.

Driving: Winter Tire Requirements

All four onsen areas involve mountain roads. Winter tires or chains are mandatory from approximately November through April, especially for Manza (1,800m elevation) and Hoshi Onsen (narrow mountain roads with sharp curves). Driving time from Tokyo ranges from 2.5 to 3.5 hours depending on the destination.

Onsen	From Tokyo	Route	Notes
Kusatsu	~2.5h	Shinkansen → JR Agatsuma Line → Bus	Most frequent connections
Takaragawa	~2.5h	Joetsu Shinkansen → Bus from Jomo-Kogen	Buses infrequent off-season
Manza	~3h	Via Kusatsu + car, or direct bus	Limited public transport
Hoshi Onsen	~3h	Joetsu Shinkansen → Bus via Minakami	Narrow mountain roads

Frequently Asked Questions

Which Gunma onsen is best for a first-time visitor?

Kusatsu is the most accessible and visitor-friendly option. It has a walkable town center, public bathhouses with English signage, restaurants, and shops — all within walking distance of the yubatake. Day-use public baths start at around ¥700 (~$5) with no reservation needed. For a more adventurous first experience, Takaragawa offers dramatic riverside outdoor baths, though it involves mixed-gender bathing.

Can I visit Takaragawa Onsen as a day trip from Tokyo?

Yes. The Joetsu Shinkansen to Jomo-Kogen Station takes about 70 minutes, followed by a 40-minute bus to Takaragawa. Day-use bathing costs ¥1,000 (~$7) for adults. Allow approximately 5-6 hours for the round trip plus bathing time. Check bus schedules in advance — service is limited, especially outside peak season.

How much does a Gunma onsen experience cost?

Day-use public baths in Kusatsu start at approximately ¥700 (~$5). Takaragawa day-use is ¥1,000 (~$7). Manza public baths are around ¥800 (~$5). Hoshi Onsen Chojukan is accommodation-only, starting at approximately ¥15,000 (~$100) per person per night with dinner and breakfast. All prices are 2024-2025 rates and may increase slightly.

Is mixed bathing (konyoku) required at Takaragawa and Hoshi Onsen?

Takaragawa's main outdoor baths are mixed-gender, though some women-only sections are available. Hoshi Onsen Chojukan's historic main bath is also mixed. Nudity is required at both — swimwear is not permitted. This is traditional Japanese communal bathing and is non-sexual in nature. If mixed bathing is a concern, Kusatsu and Manza offer gender-separated facilities.

What's the best season to visit Gunma's onsen towns?

Autumn (October-November) is ideal for Takaragawa and Hoshi Onsen, with colorful foliage surrounding the outdoor baths. Winter (December-March) is excellent for snow-viewing baths at Kusatsu and Manza, and Manza offers skiing. Spring and summer are quieter with comfortable temperatures. Every season works — onsen are year-round experiences.