Onneyu Onsen sits in Rubeshibe, about 1 hour 15 minutes from Memanbetsu Airport and around 40 minutes by car from Kitami City.

Surrounded by Akan, Daisetsuzan, and Shiretoko National Parks, it makes a practical base for exploring eastern Hokkaido. From here, you can easily plan trips to Asahikawa, Sounkyo Gorge in the Kamikawa area, the Okhotsk coast, and even the Nemuro region, all while returning to a quiet hot spring town at the end of the day.

The hot spring town dates back to 1899. “Onneyu” comes from the Ainu words onne meaning “large” and yu meaning “hot spring,” and the area was already cherished by the Ainu people long before it became known to Japanese settlers.

Today, the town is made up of three springs, Onneyu Onsen, Taki-no-Yu Onsen, and Ponyu Onsen. All are simple sulfur springs, often described in Japanese as bihada no yu, or “beauty bath,” for the way the water leaves skin feeling smooth and refreshed. For this visit, we focused on the hot spring hotels and inns clustered along the Mukagawa River in the heart of Onneyu Onsen.

Our first stop was Ōe Honke, founded in 1899, the same year Onneyu Onsen began welcoming bathers.

Located about 10 minutes by car from JR Nishi Rubeshibe Station, the inn stands along the scenic Mukagawa River. Its exterior color is said to mirror the daurian rhododendron, which blooms here in early May.

Ōe Honke has two wings, Hienkaku and Chosuikaku, offering a wide range of room types. Guests can choose from Japanese and Western-style rooms, including options with Japanese cypress bathtubs, as well as serene tatami rooms. With 174 rooms in total and pet-friendly stays available, it is a flexible choice for families and groups looking for comfort and variety.

The inn takes particular pride in its free-flowing, undiluted hot spring water drawn directly from the source. The baths are also open to day visitors, making it easy to stop in even if you are not staying overnight.

The large public bath is located in a separate annex on the west side of the Chosuikaku wing. To enter, simply purchase a ticket from the vending machine at the entrance before heading inside.

High ceilings and large windows fill the bath area with natural light during the day, creating an open and airy atmosphere. Inside, you will find a mix of large and small tubs, a Jacuzzi, a sauna, and an utaseyu, where a gentle stream of hot water cascades over your shoulders and back.

All baths use 100 percent natural hot spring water flowing directly from the source, without dilution. The temperature is carefully maintained, making it ideal for a long, unhurried soak.

The Mukagawa River is visible from the open-air bath. The bath made with natural rocks gives a feeling of unrestricted openness.

Soaking in the steady flow of natural hot spring water, not only will your skin become softer, but your body and soul will feel cleansed as well. The pleasant sound of the Mukagawa River will make you forget the time as you enjoy the comfort of the hot spring.

Tetsuji Suto, managing director of Oe Honya, is also a hot spring expert and he explained that the attractions of Onneyu Onsen are its perfect water temperature and minimal stimulation to the skin which enhance the bathing pleasure.

“The hot spring water at Onneyu Onsen is drawn from three sources and gathered in a central tank before being supplied to the inns and other facilities,” he explained. “It emerges at about 51°C (124°F), and by the time it reaches the baths it naturally cools to around 41 to 42°C, so there is no need to dilute it or adjust the temperature.”

The water is an alkaline simple hot spring, known for gently washing away dead skin cells and leaving skin feeling smooth. For that reason, it is often called a “beauty spa.”

Because the supply from the source is so abundant, the water does not need to be recirculated or filtered. This freshness and purity are part of what gives the bath its reputation for skin-friendly, rejuvenating qualities.

“Onneyu Onsen leaves a strong impression on true hot spring enthusiasts, and I believe its quality stands among the best in Hokkaido,” Mr. Suto said. “I hope visitors will come and experience its appeal for themselves.”

Taking his advice, we did just that, and quickly understood why this spring has earned such devoted praise.

When visiting Onneyu Onsen, set aside time to explore a few nearby attractions. Along Route 39, close to the Onneyu Onsen Rest Area, you will find the Northern Daichi Aquarium and the Kitakitsune Fox Farm. A bus from JR Rubeshibe Station reaches the rest area in about 20 minutes, making it an easy side trip.

Located within the rest area grounds, the Northern Daichi Aquarium showcases around 3,000 freshwater fish from about 50 species, the first facility of its kind in Hokkaido. Though compact, it features rare species not often seen elsewhere.

Highlights include Japan’s first Waterfall Basin Tank, the world’s first Frozen River Tank, and the impressive Giant Ito Tank, home to large, elusive freshwater fish. The exhibits were created by Hajime Nakamura, known for his work on the New Enoshima Aquarium and Sunshine Aquarium, and the aquarium attracts around 100,000 visitors each year.

The Four Seasons Tank recreates a riverbed beneath a frozen surface, offering a close look at fish that thrive in extreme northern climates.

Next door, the Kamurin Pavilion is home to Kamurin, the world’s largest cuckoo clock at 20 meters tall. On the hour from 8 AM to 6 PM, figures emerge to mark the time, except during winter when it is not in operation. Inside, Kamurin World features wooden toys made from Rubeshibe’s locally known timber, along with a craft studio where visitors can try simple woodworking activities. The adjacent shop carries regional specialties, making this a fun stop, especially for families.

For more details, see Northern Daichi Aquarium.

The world’s first “frozen tank” and giant phantom freshwater fish! Visit the much-talked-about Northern Daichi Aquarium!

Another popular attraction with families is the Kitakitsune Fox Farm. About 60 northern foxes are raised on the grounds where you can observe them curled up sleeping or frolicking with one another.

Another family favorite is the Kitakitsune Fox Farm, home to around 60 northern foxes. Here, you can watch them napping in the sun or playfully chasing one another across the grounds.

Located about a 3-minute drive north of the rest area, the farm is easy to spot thanks to its red roof.

Seeing the foxes up close is a memorable experience. They roam freely within the enclosed grounds, creating a relaxed, natural atmosphere. While wild northern foxes can carry parasites, the foxes here are properly cared for. That said, they are still animals and may not always approach visitors closely.

Rubeshibe Town is known as Japan’s leading producer of white flowering beans, according to a 2008 JA study. When visiting the area, stop by Fujiya Confectionery Shop, which creates a variety of sweets using this local specialty, including the popular Onneyu Onsen souvenir, Byakka Castella.

The shop is located about a 1-minute drive east of the rest area along Route 39, making it an easy addition to your itinerary.

White flowering beans contain roughly three times more fiber than burdock and are often praised for supporting digestion.

At Fujiya, you can choose from around 10 different sweets made with this local ingredient, including a creamy white flowering bean mousse made with fresh milk and cream, smooth white bean yokan jelly, and a Mont Blanc-style dessert that highlights the bean’s naturally mild sweetness.

The White Flower Castella is especially popular, featuring gently simmered white bean paste wrapped in soft, fluffy sponge cake.

These signature Onneyu sweets are also made using the area’s hot spring water, the same source used in the tanks at the Northern Daichi Aquarium, adding a uniquely local touch to each bite.

How about it? Among the many hot springs in Hokkaido Onneyu Onsen is not that well known. However, the spring water is of the best quality, something you are certain to notice when you try them.

The area has many attractions in addition to the hot springs, such as an aquarium and the Kitakitsune Fox Farm. It is also easily accessible from Asahikawa and the Okhotsk region making it convenient and easy to visit.

Text: Etsuro Nagao