The Hot Springs of Oigami
Abundant Natural Springs and Gentle Water
Oigami Onsen is currently known to have eight natural hot spring sources. In the past, there were as many as 15 sources, producing a remarkable total of approximately 1,150 liters of hot spring water per minute.
One of the representative spring types is a simple hot spring, with a source temperature of approximately 61.5°C. The water is known for its gentle feel on the skin and smooth sensation when bathing.
Traditional descriptions of the springs associate them with relief from conditions such as dry skin, chronic rheumatism, muscle pain, neuralgia, nerve inflammation, wounds, and hives. For generations, Oigami has therefore been affectionately associated with the idea of a “hot spring for the skin.”
These traditional descriptions reflect the historical reputation of the hot springs and should not be regarded as a substitute for medical treatment.
A Variety of Natural Spring Sources
Several different spring sources are used throughout the resort, including Oigami No. 1, No. 3, No. 5, No. 7, No. 8, and No. 10, as well as Kannon Yakuyu and Wakano-yu No. 3.
The springs differ somewhat in their mineral characteristics and temperatures. In addition to simple hot springs, the area includes simple sulfur springs and alkaline simple hot springs.
Because individual accommodations may draw water from different sources, guests can sometimes enjoy subtle differences in the character of the water from one lodging facility to another.
Although the number of accommodations in Oigami has decreased in recent years, the overall volume of spring water has remained relatively stable. As a result, more hot spring water can be supplied to each remaining facility, contributing to Oigami’s reputation among hot spring enthusiasts for the quality of its bathing experience.
A Quiet Hot Spring Town Surrounded by Mountains
Oigami Onsen lies in a beautiful natural setting surrounded by mountains such as Mount Sukai and Mount Nikkō-Shirane. The clear waters of the Katashina River flow through the valley, with traditional inns and hotels lining the river.
The landscape changes beautifully throughout the year, offering a peaceful atmosphere where visitors can slow down and enjoy the natural surroundings.
The hot spring area extends across the districts of Oigami, Anabara, and Taiyo in Tone Town. The resort is surrounded by rivers, fields, and mountain scenery, giving it a distinctly rural atmosphere.
In 1935, Oigami Onsen, Anabara Onsen, and Taiyo Onsen formed an association and adopted the name Oigami Onsenkyo, referring to the wider hot spring resort area.
At its peak in 1983, approximately 22 lodging facilities operated in the resort. Today, around 13 remain. While Oigami is not as internationally famous as major Gunma hot spring destinations such as Kusatsu or Ikaho, its relatively quiet atmosphere allows visitors to enjoy the mountains and hot springs at a more relaxed pace.
The overwhelming majority of guests are Japanese, making Oigami particularly suited to travelers seeking a tranquil environment in which to experience traditional Japanese hot spring culture and nature.
Seasonal Festivals and Events
Orochi Festival – May
The biggest annual event at Oigami Onsen is the Orochi Festival, held each year on the second Friday and Saturday of May.
The highlight is a gigantic serpent measuring approximately 108 meters long and weighing around 2 tons. More than 200 people carry the enormous serpent through the hot spring town, creating an impressive spectacle.
Food stalls and other nighttime attractions also appear during the festival, filling the normally quiet resort with an energetic atmosphere.
Oigami Morning Market – Late April to Mid-November
The local morning market is held every day from approximately 6:00 to 7:30 a.m. and is sometimes described as one of the finest morning markets in the Kanto region.
Local vendors offer fresh vegetables, mountain vegetables, miso, pickles, kusa-mochi rice cakes, and other regional foods. The market provides a wonderful opportunity to experience the flavors of the surrounding mountain communities and interact with local residents.
Other Seasonal Events
Oigami Onsen hosts a variety of events throughout the year, including Setsubun celebrations, winter fireworks, elaborate hina-doll displays, poppy festivals, summer fireworks, and soba festivals.
These events add seasonal character to the resort and provide visitors with opportunities to experience local traditions alongside the hot springs.
The Legend Behind the Name “Oigami”
A Battle Between Mountain Gods
The history of Oigami Onsen is closely connected with a dramatic local legend involving two powerful mountain deities.
According to the legend, the god of Mount Akagi in ancient Kōzuke Province, corresponding roughly to present-day Gunma Prefecture, fought the god of Mount Nikkō-Nantai, or Futara, in the Senjōgahara area of present-day Tochigi Prefecture.
The god of Mount Akagi was said to have transformed into a giant serpent, while the god of Mount Futara took the form of a gigantic centipede. Their fierce battle eventually left the god of Mount Akagi wounded by an arrow.
The wounded deity fled toward the foothills of Mount Akagi. There, he drove an arrow into the ground. According to the legend, hot spring water suddenly emerged from the spot. When the god immersed his wounds in the water, they were miraculously healed.
Restored to strength, he returned to the battle and drove the god of Mount Futara away.
The name “Oigami” is traditionally said to have developed from “Oigami,” meaning “the pursuing god”, referring to the deity who chased his rival away. This legendary story remains an important part of the cultural identity of the hot spring town.
Akagi Shrine and Futara Shrine
Two shrines associated with the legend can still be found around the resort. Futara Shrine stands on the eastern side of the Katashina River, while Akagi Shrine stands on the western side.
Both are cherished by the local community as places that preserve the legendary story behind Oigami Onsen.
A Gateway to Oze
Oigami Onsen is also an important gateway to Oze, one of Japan’s most celebrated natural landscapes.
During the Oze hiking season, the Oigami Onsen Oze Hiking Bus operates services providing convenient access toward Hatomachi Pass, one of the main gateways to the Oze area.
Staying overnight at Oigami before or after hiking in Oze allows travelers to enjoy the mountains at a relaxed pace. After a day of walking through Oze’s wetlands and mountain landscapes, soaking in a hot spring is an especially pleasant way to rest.
Nearby Attraction: Fukiware Waterfalls
Not far from Oigami Onsen is Fukiware Waterfalls, one of Gunma Prefecture’s most spectacular natural attractions. Often called the “Niagara of the Orient,” the waterfall flows dramatically through a unique geological formation.
Visitors can view the falls safely from the surrounding walking trails and observation platforms. The trail is generally closed during the winter season, while spring through autumn are popular times to explore the gorge.
Combining Fukiware Waterfalls with a stay at Oigami Onsen makes for an excellent itinerary in the Oze and Numata area.
Access to Oigami Onsen
By Train and Bus
From JR Jōetsu Shinkansen Jōmō-Kōgen Station, take a Kan-Etsu Kotsu local bus. The journey takes approximately 70 minutes.
From JR Jōetsu Line Numata Station, the journey by Kan-Etsu Kotsu bus takes approximately 50 minutes.
By Car
From the Numata Interchange of the Kan-Etsu Expressway, Oigami Onsen is approximately 25 minutes by car.
Some accommodation facilities also provide pickup services from nearby railway stations, so guests should check directly with their chosen hotel or ryokan when making a reservation.
Relaxing in the Mountains of Gunma
Oigami Onsen is a traditional hot spring resort where legends, natural scenery, and abundant spring water come together in a peaceful mountain setting.
Unlike larger and busier hot spring destinations, Oigami offers an atmosphere centered on quiet relaxation, nature, and traditional bathing culture. Visitors can soak in gentle hot spring water while listening to the sound of the Katashina River and taking in the surrounding mountain scenery.
The resort is also an excellent base for exploring attractions such as Oze and Fukiware Waterfalls. A visit can therefore combine hiking, spectacular natural landscapes, local festivals, traditional Japanese culture, and the simple pleasure of relaxing in a hot spring.
For travelers looking for a quieter side of Japan away from the country’s busiest tourist destinations, Oigami Onsen offers a memorable mountain retreat where the atmosphere is calm, the scenery is beautiful, and local legends remain part of everyday life.