Gomi Onsen (五味温泉)

Introduction: The Forest Sanctuary of Naturally Effervescent Waters

Deep within the “Eco-Village” of Shimokawa Town, tucked away in the serene forests of the Kamikawa region, lies Gomi Onsen (五味温泉). This hot spring is a true geological rarity in Japan: a high-concentration, naturally carbonated spring. Often referred to as “The Champagne of the Forest,” Gomi Onsen offers a therapeutic experience that feels as if you are submerged in a giant glass of sparkling mineral water. For the international traveler, Gomi Onsen represents the intersection of Hokkaido’s commitment to sustainable forest management and the raw healing power of volcanic gases. It is a place of profound silence, where the air is scented with fresh pine and larch, and the effervescent waters provide a unique circulatory boost. Whether you are an “Onsen Hunter” seeking Japan’s rarest water types or a nature lover looking for a digital detox in a model eco-community, Gomi Onsen is an essential northern retreat.

Key Information Table

The Healing Waters: The Bohr Effect and the “Champagne” Soak

The water at Gomi Onsen is a Naturally Carbonated Spring, a phenomenon found in only a few dozen locations across Japan. The water is rich in dissolved carbon dioxide gas.
The Science of Circulation: When you soak in carbonated water, the CO2 is absorbed transdermally. Your body interprets this increase in CO2 as a sign of metabolic activity and responds by dilating blood vessels to rush oxygen to the area. This is known as the “Bohr Effect.” It results in a dramatic increase in circulation without taxing the heart, making it ideal for treating hypertension and cold sensitivity (Hiesho).
The facility features three tubs at different temperatures: the unheated “Source Tub” (cool) where you can feel the tiny bubbles adhering to your skin, and the heated tubs for comfort. The water has a slight, pleasant mineral aroma and leaves the skin feeling notably smooth and tight.

Top Recommended Stay: Gomi Onsen (The Forest Lodge)

• Gomi Onsen (下川町五味温泉): This is the only accommodation in the immediate area. It is a warm, wooden structure that feels like a European mountain chalet. The rooms are clean and offer peaceful views of the surrounding larch forest. The lodge is famous for its “Shimokawa Udon” dinners and its use of biomass energy (wood pellets) to heat the baths, reflecting the town’s eco-philosophy. It is a favorite for those seeking a quiet, intellectual retreat.

Must-Visit Neighborhood Spots: Forest Therapy and Woodwork

Ichinohashi Bio-Village: A model community near the onsen that showcases sustainable living, including medicinal herb greenhouses and biomass heating systems.
Shimokawa Hand-stretched Udon (Tenobe Udon): Visit the local workshops to see the traditional technique of hand-stretching noodles. These noodles are famous for their silky texture and “koshi” (chewiness).
The Great Forest Walk: Shimokawa is a leader in “Forest Therapy.” Guided walks are available through the town’s FSC-certified forests, ending with a restorative soak at Gomi Onsen.

Local Gastronomy: The Bounty of the “Udon Town”

Shimokawa’s food is defined by its pristine water and its sustainable forestry.
Shimokawa Tenobe Udon: The signature local dish. The noodles are stretched over 2 meters long by hand.
Forest Herbs: The onsen restaurant serves dishes featuring locally grown medicinal herbs like chamomile and rosemary.
Vegetarian/Vegan Survival: Shimokawa is an excellent place for plant-based travelers.
For Vegans: The Shimokawa Udon can be served with a simple mushroom broth or just olive oil and salt—specify “Katsuo-dashi nuki” (No fish dashi). The local Handmade Tofu is rich and creamy. In summer, the town produces incredible Cherry Tomatoes that are sweet like candy and 100% vegan snacks.

Cultural & Historical Context

Gomi Onsen was discovered in the late Meiji era by a pioneer named Mr. Gomi, who noticed that animals often gathered at a bubbling spring in the forest to heal their wounds. For decades, it was a simple, rustic “Toji” (healing) site. In the 21st century, the town of Shimokawa incorporated the onsen into its vision for a “Future City”—a sustainable community powered by its own forests. The onsen now serves as a symbol of the town’s circular economy, using waste wood from the timber mills to heat the therapeutic springs.

Practical Travel Tips for International Visitors

• Tattoo Policy: Gomi Onsen is very community-oriented and generally tolerant of international guests. Small tattoos are usually fine. For large pieces, we recommend covering them with patches or visiting during the early afternoon on weekdays when it is less crowded.
• Eco-Friendly Initiatives: The onsen encourages guests to be mindful of water usage. Amenities are simple but high-quality; we recommend bringing your own skincare if you have specific requirements.
• Language Support: Basic English information is available at the front desk. The town of Shimokawa is very progressive and used to hosting international environmental researchers.
• Cash Only: The day-trip bath tickets and the local udon stalls are strictly cash-only (JPY). The main lodge accepts credit cards for overnight stays.
• Access Advice: If you are traveling by train, get off at JR Nayoro Station. From there, a community bus runs to Shimokawa center, and a secondary bus (infrequent) goes to the onsen. A rental car from Asahikawa is much more convenient.

2025-2026 Latest Updates

In 2025, Gomi Onsen launched a “Biomass & Wellness Tour,” where guests can tour the heating facility and learn about the Bohr Effect before their bath. For the 2026 season, new “Forest Meditation Decks” are being built in the woods adjacent to the lodge, allowing for outdoor yoga sessions that complement the thermal therapy.

Safety & Manners

In the carbonated bath, do not stay in the water too long if you feel lightheaded, as the vasodilation effect is quite powerful. Always sit on the provided stools while washing. Because the facility is in a deep forest, be “Bear Aware”—carry a bear bell if you are exploring the forest trails alone. Finally, respect the quiet; Gomi Onsen is a place for healing the heart and mind, so keep conversations in the communal baths to a soft whisper.