Hirugami Onsen, Nagano Prefecture | Complete Guide 2026: Enjoying Japan’s Best Starry Sky and Skin-Beautifying Hot Spring
Hirugami Onsen, located in Achi Village, Shimohina County, Nagano Prefecture, is a hot spring resort known nationally for its “Japan’s Best Starry Sky” and “Skin-Beautifying Hot Spring.” This mountain hot spring area, which spreads along the Achi River flowing at the southern end of the Central Alps, captivates many tourists with its spectacular scenery created by abundant nature, high-quality hot spring water, and a sky full of stars.
This article provides a thorough explanation of everything you need to know before visiting Hirugami Onsen, from its attractions to specific access methods, recommended accommodations, surrounding tourist spots, and seasonal ways to enjoy it.
What is Hirugami Onsen? History and Characteristics
Discovery and History of the Hot Spring
The history of Hirugami Onsen is relatively recent, beginning in 1973 (Showa 48) when the hot spring accidentally gushed out during tunnel excavation work for the construction of the JNR Nakatsugawa Line (currently not in operation). Legends remain of hot springs existing before this time, but details are unclear.
Despite its relatively short history of just over 50 years since its discovery, the high-quality hot spring water combined with the abundant natural environment of Achi Village has led to its rapid development as a representative hot spring resort in Southern Shinshu. Currently, approximately 20 inns and hotels line the area, making it a major hot spring resort that attracts many tourists throughout the year.
Hot Spring Quality and Benefits | Why It’s Famous as a Skin-Beautifying Hot Spring
Hirugami Onsen’s hot spring water is an alkaline simple sulfur spring with a high pH value, earning high praise as a skin-friendly “skin-beautifying hot spring.” It is characterized by being colorless and transparent with a silky texture, and it is renowned that skin becomes smooth and soft after bathing.
Main Benefits:
- Neuralgia, muscle pain
- Joint pain, frozen shoulder
- Motor paralysis, joint stiffness
- Bruises, sprains
- Chronic digestive disorders, hemorrhoids
- Poor circulation, post-illness recovery
- Fatigue recovery, health improvement
Particularly popular among women, it is highly rated in word-of-mouth as a hot spring where you can become a “beautiful woman fresh from the bath.” Abundant hot spring water is also a characteristic of Hirugami Onsen, with the public hot spring facility of Achi Village, Tsurumaaki-so, being particularly famous locally as “the most concentrated hot spring in Hirugami Onsen.”
Japan’s Best Starry Sky | Achi Village’s Heaven-Like Spectacle
Environment Ministry-Certified “Place Where Stars Shine Most Brightly”
Achi Village was certified as the “#1 place where stars shine most brightly” in the nationwide starry sky continuous observation survey conducted by the Environment Ministry in 2006. This title of “Japan’s Best Starry Sky” has become a major attraction for both Hirugami Onsen and Achi Village.
In Achi Village, where three conditions coincide—high altitude, minimal light pollution from surrounding areas, and clear air—a sky full of stars can be observed on clear nights. The Milky Way appears distinctly, and the probability of spotting shooting stars is extremely high.
Tenku no Rakuen Night Tour Season 2026
The “Tenku no Rakuen (Paradise of Heaven) Night Tour” is the definitive choice for stargazing and has become popular. The 2026 season’s operation has been confirmed, and visitors can ride a ropeway up to Fujimi Daira Highland and enjoy a 360-degree panoramic starry sky at an altitude of 1,400 meters.
Night Tour Features:
- Gondola ride to the summit with a total length of 2,500m and travel time of approximately 15 minutes
- Explanations provided by stargazing guides
- Observe different constellations and celestial phenomena depending on the season
- Cold-weather measures and stargazing equipment rental available
The charm of being able to enjoy two attractions—hot springs and starry sky—at once is the highlight of staying in Hirugami Onsen. Many inns also offer reservation agency services for stargazing tours.
How to Access Hirugami Onsen
Access by Car
From Tokyo:
- Approximately 5 minutes from the “Sonohara IC” on the Chuo Expressway (nearest interchange)
- Approximately 30 minutes from the “Iida IC” on the Chuo Expressway
- Travel time: Approximately 3.5 hours from Tokyo
From Nagoya:
- Approximately 5 minutes from the “Sonohara IC” on the Chuo Expressway
- Travel time: Approximately 1.5 hours from Nagoya
From Osaka:
- Approximately 4 hours via the Chuo Expressway
Since it is close to the Sonohara IC, access by car is extremely convenient. Parking lots at each inn are available in the hot spring resort area.
Access by Public Transportation
Train + Bus:
- Get off at “Iida Station” on the JR Iida Line
- Take the Shinnan Bus “Hirugami Onsen-bound” for approximately 30 minutes
- Get off at the “Hirugami Onsen” bus stop
Highway Bus:
- Highway bus directly from Shinjuku to Hirugami Onsen (approximately 4 hours)
- Access to Hirugami Onsen possible from Nagoya via Iida
When using public transportation, some inns offer shuttle service from Iida Station, so it is recommended to confirm this at the time of booking.
Recommended Inns and Hotels | How to Choose Accommodations
Hirugami Onsen offers a diverse range of accommodations that can be chosen according to budget and purpose.
Luxury Inns and Resort Hotels
Characteristics:
- Equipped with panoramic large-scale baths and garden open-air baths
- Modern and Japanese-style facilities such as 7-story buildings with good views
- Kaiseki cuisine and authentic Japanese meals using local ingredients
- Dedicated stargazing observation space
Many modern Japanese-style inns stand along the Achi River, allowing guests to view the changing seasons of nature from their rooms. Autumn leaves and fresh greenery are particularly spectacular.
Budget-Friendly Inns and Public Accommodations
Tsurumaaki-so (Shinshu Public Accommodation):
As a public hot spring facility in Achi Village, it is famous locally for its abundant hot spring water and is known as “the most concentrated hot spring in Hirugami Onsen.” A purely Japanese-style inn that values human warmth and kindness, offering excellent value for money.
Modern Accommodations
Achi no Sato Hirugami:
With the concept of “a lodging where you see cherry blossoms and stars in an open-air bath,” this modern accommodation nestled in the mountains is popular. It is characterized by sophisticated spaces popular with younger generations and couples.
Points for Choosing an Inn
- Type of Hot Spring: Confirm facilities such as open-air baths, panoramic baths, and private baths
- Meals: Presence or absence of local ingredients such as Shinshu beef, river fish, and mountain vegetables
- Stargazing: Presence or absence of rooftop observation decks and stargazing tour shuttles
- Location: Landscape along the Achi River, convenience of access
- Price: Wide range from 10,000 yen in the teens to over 30,000 yen for one night with two meals
Day-Trip Hot Spring Facilities | Enjoying Hirugami’s Hot Spring Casually
Yu-ttari~na Hirugami
The most popular day-trip hot spring facility in Hirugami Onsen is “Yu-ttari~na Hirugami.”
Facility Information:
- Address: 4092-7 Satotori, Achi Village, Shimohina County, Nagano Prefecture
- Access: 4-minute walk from Hirugami Onsen bus stop
- Hours: Open year-round (except for maintenance days)
- Fee: Approximately 600 yen for adults (varies by season)
Facility Features:
- High-quality hot spring water gushing out across the clear Achi River
- Enjoy the nature of Hirugami Onsen from an open-air bath
- Indoor bath and sauna also available
- Pool facility also available (summer season)
- Rest areas and dining services available
This is an ideal facility to stop by during sightseeing or before and after staying at an inn. It is a popular spot frequently used by local residents as well.
Other Day-Trip Bathing Facilities
Many inns and hotels also accept day-trip bathing. Since advance reservations are required in some cases or visiting hours may be limited, it is recommended to call each facility in advance to confirm.
Hana Momo no Sato | Spring’s Scenic Spot
Japan’s Number One Peach Blossom Paradise
Achi Village is also nationally famous as the “Hana Momo no Sato (Cherry Blossom Village).” From mid-April to early May each year, approximately 5,000 ornamental peach blossoms bloom all at once, creating a breathtaking landscape like a peach blossom paradise with red, white, and pink colors weaving together.
Scenic Spots:
- Tsukigawa Onsen Resort Area: Hana Momo (peach blossom) Boulevard spanning approximately 40 hectares
- Hirugami Onsen Street: Ornamental peach tree-lined streets coloring the hot spring resort
- Sonohara Area: Peach blossom cluster in mountainous areas
Hana Momo Cafe (ACHIBASE Limited-Time Opening)
During the period from March 20 (Friday) to June 30 (Tuesday), 2026, “Hana Momo Cafe” will open at the dining space of the tourist facility “ACHIBASE (Achi Base).”
Charm of Hana Momo Cafe:
- Space design inspired by Japan’s number one peach blossom paradise
- Original sweets with peach blossoms as a motif
- Light meal menus using local ingredients
- Perfect rest stop for peach blossom viewing
ACHIBASE is also an information dissemination center for Hirugami Onsen and Achi Village tourism, offering services such as tourism information, local specialty sales, and bicycle rentals.
Surrounding Tourist Spots | Enjoying Alongside Hirugami Onsen
Tsukigawa Onsen
Located approximately 10 minutes by car from Hirugami Onsen, Tsukigawa Onsen is another representative hot spring resort in Achi Village. It is recommended for those who prefer a quieter environment surrounded by nature and is also located in the center of the Hana Momo Boulevard.
Heavens Sonohara (Fujimi Daira Highland)
A high-altitude resort at 1,400 meters that can be enjoyed throughout the four seasons.
Spring to Summer:
- Observation of alpine plants such as skunk cabbage and Japanese false hellebore
- Trekking courses
- Spectacular views from observation platforms (views of the Central and Southern Alps)
Autumn:
- Famous for autumn foliage
- Sea of clouds viewing
Winter:
- Operates as a ski resort
- Winter starry sky viewing
Sato Ogo Area | Winery Tours
In the Sato Ogo area of Achi Village, wine production has become popular in recent years. In 2026, sales began for two types of Sato Ogo apple wines, “CYGNUS” and “PEGASUS,” which have drawn attention.
Winery tours and tasting sessions are available at various facilities, making it popular as an upscale travel plan combining hot springs and wine.
Camping Grounds and Outdoor Facilities
Achi Village has multiple camping grounds, allowing for active stays in nature.
Recommended Points:
- Camping experience under the starry sky
- River play and barbecue
- Family-friendly auto-camping grounds
- Glamping facilities also available
A new way to enjoy the experience called “hot spring camping,” combining hot springs and camping, is also being proposed.
Seasonal Ways to Enjoy | Annual Event Calendar
Spring (March to May)
Hana Momo Festival (mid-April to early May):
- Approximately 5,000 ornamental peach blossoms bloom
- Hana Momo Boulevard drive
- Hana Momo Cafe opens (from March 20)
- Photography spot tours
Summer (June to August)
Stargazing Season:
- Tenku no Rakuen Night Tour begins in earnest
- Peak season for viewing the Milky Way
- Firefly viewing (late June to early July)
- Stay in a summer retreat
- River play, camping
Autumn (September to November)
Autumn Foliage Season (mid-October to early November):
- Autumn foliage along the Achi River
- Heavens Sonohara autumn foliage ropeway
- New soba noodle season
- Autumn starry sky viewing (clearer and more beautiful air)
Winter (December to February)
Winter Starry Sky and Snow Landscape:
- Season when stars appear most beautifully
- Snow-viewing open-air bath
- Skiing and snowboarding (at Heavens Sonohara)
- Winter cuisine (game meat dishes, etc.)
Gourmet Information | Savoring Local Flavors
Shinshu Soba
Shinshu soba is representative gourmet fare of Nagano Prefecture. There are numerous soba restaurants in the Achi Village area, where you can taste fragrant soba made with local soba flour.
Goheimochi
Goheimochi, a local dish of Southern Shinshu, is also popular as a street food in Hirugami Onsen. It is characterized by its sweet and spicy sauce and is perfect as a companion for strolling through the hot spring resort.
Shinshu Beef and Game Meat
High-end inns’ kaiseki meals feature Shinshu beef steak and sukiyaki. In winter, game meat dishes such as venison and wild boar are also available.
River Fish Cuisine
River fish dishes made with fish such as char and sweetfish caught in the Achi River are also local specialties. Cooking methods that highlight the natural flavors, such as salt grilling and sweet glaze, are characteristic.
Local Sake and Wine
Nagano Prefecture is also famous for sake production, and sake from local breweries can be enjoyed at each inn. Ogo apple wines mentioned above and other locally produced wines are also gaining attention.
Hirugami Onsen Tourism Base | ACHIBASE (Achi Base)
ACHIBASE is a comprehensive tourism base facility for Achi Village and Hirugami Onsen that opened in 2020.
Main Functions:
- Tourist information center (multilingual support)
- Local specialty sales corner
- Cafe and light meal space
- Bicycle rentals
- Electric-assist bicycle rentals
- Event space
- Rest areas
Access:
Located in the center of Hirugami Onsen and within walking distance of most inns.
Gathering tourism information, checking regional notices, purchasing souvenirs—this is a convenient facility you’ll want to visit multiple times during your stay. Friendly staff provide detailed tourism guidance, so first-time visitors are recommended to stop by ACHIBASE first.
Tips for Booking Accommodations in Hirugami Onsen
Booking Timing and Seasons
High Season (Early Booking Recommended):
- Golden Week (peach blossom season)
- Obon holidays
- Autumn foliage season (mid-October to early November)
- New Year holidays
During these periods, reservations begin filling up three months in advance. Popular inns begin accepting reservations six months ahead.
Off-Season (Budget-Friendly Stays):
- January to February (beautiful winter starry sky but cold)
- June (rainy season but stargazing still possible)
- Late November to mid-December
Booking Site Comparisons
- Rakuten Travel: High reward point rates and abundant reviews
- Jalan.net: Many exclusive plans and Ponta points can be earned
- Yuko Yuko: Comprehensive plans for middle-aged and older travelers, detailed hot spring information
- Official Website: Direct discount offers and special plans may be available
Points to Check
- What’s Included in Price: Breakfast only, two meals included, unlimited drinks or not
- Room Type: Japanese-style, Western-style, private open-air bath in room
- Cancellation Policy: When free cancellation is possible
- Shuttle Service: Whether shuttle service from Iida Station is available
- Stargazing Tour: Whether night tour tickets are included in the package
Packing List for Hirugami Onsen Trip
Essentials
- Identification
- Booking confirmation (email screenshot, etc.)
- Cash (some facilities do not accept cashless payment)
- Smartphone and charger
- Medications
For Stargazing
- Warm clothing (cold even in summer at night)
- Flashlight (smartphone light is also acceptable)
- Camera and tripod (if photographing stars)
- Leisure sheet (if sitting on ground for viewing)
Hot Spring Use
- Towel (provided by inn, but bring for day-trip hot springs)
- Skincare products
- Plastic bag (to put wet towels in)
By Season
Spring (Peach Blossom Season):
- Camera (for photographing peach blossoms)
- Comfortable walking shoes (for strolling)
- Light outerwear (for early morning and evening chill)
Summer:
- Insect repellent spray
- Sunscreen
- Hat
- Swimsuit (if visiting a facility with pool)
Autumn (Foliage Season):
- Jacket
- Trekking shoes (if hiking)
Winter:
- Down jacket
- Gloves and scarf
- Disposable hand warmers
- Non-slip shoes
Latest Topics about Hirugami Onsen 2026
Tenku no Rakuen Night Tour Season 2026 Operation
The 2026 season’s operation of the “Tenku no Rakuen Night Tour” has been confirmed. New productions and stargazing explanation programs are planned to be added, creating content that returning visitors can also enjoy.
Hana Momo Cafe Limited-Time Opening
As mentioned above, “Hana Momo Cafe” will open at ACHIBASE from March 20 to June 30, 2026. It proposes a new way to enjoy the peach blossom season in Japan’s number one peach blossom paradise.
New Ogo Apple Wine Products
Two types of Ogo apple wines, “CYGNUS (Swan constellation)” and “PEGASUS (Pegasus constellation)” named after constellations, have begun sales. With naming befitting the star village, they are popular as souvenirs.
Reinforced Multilingual Support
Tourist facilities including ACHIBASE have reinforced multilingual support with simplified Chinese, traditional Chinese, English, and other languages, and the number of international tourists is increasing.
Nature and Activities Around Hirugami Onsen
Trekking and Hiking
The Achi Village area has diverse trekking courses that can be enjoyed by beginners to advanced hikers.
Recommended Courses:
- Fujimi Daira Highland Hiking Course (beginner to intermediate)
- Sonohara Village Stroll Course (beginner)
- Central Alps Climbing Route (advanced)
Cycling
Renting bicycles or electric-assist bicycles from ACHIBASE and cycling around the hot spring resort or the peach blossom boulevard is also popular. The ride is exhilarating while feeling nature’s breeze.
River Play and Fishing
In summer, river play and stream fishing can be enjoyed in the Achi River. Safe river play spots are particularly popular with families with children.
Photography Spots
The area around Hirugami Onsen is full of photography spots.
Popular Photography Spots:
- Peach blossom boulevard (spring)
- Landscape of Achi River and hot spring resort
- Starry sky (Heavens Sonohara)
- Autumn foliage gorge (autumn)
- Snowy landscape and hot spring resort (winter)
There are many posts on social media such as Instagram, with many beautiful photos visible using hashtags such as “#Hirugami Onsen,” “#Achi Village,” and “#Japan’s Best Starry Sky.”
Sample Courses in Hirugami Onsen
Classic 1-Night 2-Day Course
Day 1:
- 12:00 Arrive at Hirugami Onsen, check-in
- 13:00 Stroll through hot spring resort, visit ACHIBASE
- 15:00 Bathe in hot spring at inn
- 18:00 Dinner (kaiseki cuisine)
- 20:00 Participate in Tenku no Rakuen Night Tour (stargazing)
- 22:00 Return to inn, late snack and rest
Day 2:
- 7:00 Breakfast
- 9:00 Check-out
- 9:30 Tsukigawa Onsen and Peach Blossom Boulevard drive (spring season)
- 11:00 Tour Heavens Sonohara
- 13:00 Lunch at a soba restaurant
- 14:00 Head home
Fully Immersive 2-Night 3-Day Course
In addition to the 1-night 2-day course:
- Tour Sato Ogo winery district
- Trekking and hiking
- Visit surrounding tourist spots (such as Iida City)
- Tour multiple day-trip hot spring facilities
Day-Trip Course
- 10:00 Arrive at Hirugami Onsen
- 10:30 Visit ACHIBASE, gather tourism information
- 11:00 Stroll hot spring resort, eat goheimochi
- 12:00 Lunch at soba restaurant
- 13:30 Day-trip bathing at Yu-ttari~na Hirugami
- 15:00 Purchase souvenirs
- 16:00 Head home
Souvenirs and Local Products of Hirugami Onsen
Standard Souvenirs
- Hot Spring Cakes: Hirugami Onsen original hot spring cakes
- Goheimochi (frozen or vacuum-packed): Can heat and eat at home
- Shinshu Soba: Dried noodles, fresh noodles, and various types
- Local Sake: Sake from local breweries
- Apple Wine: Wine produced in Sato Ogo district
Unique Souvenirs
- Starry Sky Goods: Star finder disks, star postcards, etc.
- Peach Blossom Products: Peach blossom jam, honey, etc.
- Hot Spring Cosmetics: Cosmetics using hot spring water from Hirugami Onsen
- Game Meat Products: Venison jerky, etc.
Places to Purchase
- ACHIBASE (extensive selection)
- Shop at each inn
- Shop at Yu-ttari~na Hirugami
- Rest areas (in surrounding regions)
Conclusion | Maximizing the Charm of Hirugami Onsen
Hirugami Onsen in Achi Village, Nagano Prefecture, has three major charms: “Japan’s Best Starry Sky,” “Skin-Beautifying Hot Spring,” and “Peach Blossom Paradise.” Combined with the convenience of being just about 5 minutes from the Sonohara IC on the Chuo Expressway, it is popular with tourists from Tokyo, Nagoya, Osaka, and other regions.
Hirugami Onsen is Particularly Recommended For:
- Those who love stargazing and want to photograph the sky
- Those who want to relax in high-quality hot springs
- Those who want to be healed in a natural-rich environment
- Those who want to enjoy seasonal landscapes like spring peach blossoms and autumn foliage
- Those who want to experience Shinshu’s food culture
With diverse attractions including hot springs, starry sky, nature, gourmet food, and activities, Hirugami Onsen offers various ways to enjoy depending on the season of visit and length of stay, which is why it has many repeat visitors.
Tourism base facilities such as ACHIBASE are well-equipped, allowing first-time visitors to enjoy sightseeing with peace of mind. As new events and services are planned for 2026, it continues to evolve into an increasingly attractive hot spring resort.
Leave behind the hustle and bustle of daily life and experience a special time healed by the starry sky and skin-beautifying hot springs at Hirugami Onsen.
