Sanka Onsen (三香温泉)

Introduction: The Secret Garden Sanctuary and the Silky Waters of the Birch Forest

Tucked away in a quiet forest clearing near the southern shores of Lake Kussharo, Sanka Onsen (三香温泉) is a destination that feels like a private secret. While many travelers head to the more famous Kotan or Sunayu baths, those seeking absolute tranquility and high-quality mineral water find their way to this single-inn retreat. Sanka Onsen is defined by its stunning hand-tended gardens and its location amidst a primeval forest of white birch and Japanese oak. For the international traveler, Sanka Onsen represents the “Sophisticated Rural” side of Hokkaido. It is a place where the hospitality is intimate, the air is scented with forest blossoms, and the thermal waters—rich in bicarbonate—provide a deep, silky cleansing that leaves the skin feeling renewed. If you are looking for a quiet, intellectual retreat where you can listen to the wind in the trees while submerged in the earth’s bounty, Sanka is your northern oasis.

Key Information Table

The Healing Waters: The Organic Silk of the Forest

The water at Sanka Onsen is celebrated among connoisseurs for its absolute purity and its high bicarbonate concentration. The spring is 100% natural flow (Gensen Kakenagashi), used without any heating or dilution. The water is crystal clear and notably “slippery” or “thick” to the touch. The alkalinity acts as a natural cleanser, emulsifying skin oils and gently removing old keratin—this is the definitive “Bijin-no-yu” (Beauty Water). The highlight of the facility is the Outdoor Rotenburo, which is surrounded by the inn’s famous gardens. In spring, you soak amidst blooming flowers; in winter, you are enveloped in a silent world of white birches and falling snow. The minerals are particularly effective at improving peripheral circulation, making it a favorite for hikers returning from the nearby mountain trails.

Top Recommended Stay: Sanka Onsen Ryokan

• Sanka Onsen Ryokan (三香温泉旅館): A small, family-run inn that feels more like a private home than a hotel. It offers a limited number of traditional Japanese rooms, ensuring a quiet stay. The inn is famous for its home-cooked meals featuring “Kussharo Bounty”—seasonal mountain vegetables, fresh lake fish, and Hokkaido-grown rice. It is the perfect base for writers, photographers, and couples seeking a “Digital Detox” in a beautiful botanical setting. Note: Guest rooms share communal onsen facilities; the atmosphere is one of respectful communal living.

Must-Visit Neighborhood Spots: Forests and Horizons

The Sanka Garden: The inn’s private garden is a destination in itself. Meticulously maintained, it features a variety of Hokkaido flora that changes dramatically with the seasons.
Lake Kussharo Shoreline: A short walk through the woods leads to a quiet, undeveloped stretch of the lakeshore, perfect for private meditation or birdwatching.
Wagoto Peninsula Trail: A 10-minute drive away, this 1-hour circular hiking trail features volcanic vents and spectacular lake views.
Mt. Io (Atosanupuri): A 15-minute drive to see the steaming yellow sulfur vents of the “Naked Mountain.”

Local Gastronomy: The Slow Food of Teshikaga

Food at Sanka is honest, rustic, and locally sourced.
Sansai (Mountain Vegetables): In spring and summer, the meals feature wild ferns and roots gathered from the surrounding birch forest.
Lake Smelt (Wakasagi): Freshly caught and served in light, crispy tempura.
Vegetarian/Vegan Survival:
For Vegans: Being a small inn, the menu is fixed. You must notify them at least 5 days in advance if you are vegan. They can prepare incredible vegetable-only meals using the “Teshikaga Gold” potatoes and local corn. For a casual meal nearby, visit the Teshikaga Michi-no-Eki for fresh, ready-to-eat vegetable snacks. The local **”Inca-no-Mezame”** potatoes are so sweet they taste like chestnuts—highly recommended.

Cultural & Historical Context

Sanka Onsen was founded by a family of pioneers who fell in love with the specific quality of the water in this forest clearing. They built the lodge with their own hands, prioritizing a harmonious relationship with the forest over commercial growth. The name “Sanka” (Three Fragrances) refers to the scents of the forest, the garden, and the spring water itself. Today, it remains one of the few places in the national park where you can experience the “pioneer-style” of onsen culture in a refined and well-cared-for environment.

Practical Travel Tips for International Visitors

• Tattoo Policy: Sanka Onsen is very quiet and traditional. Small tattoos are fine; for large pieces, we recommend using the bath during early afternoon or late evening when other guests are fewer. As it is a small inn, a polite inquiry at check-in is always appreciated.
• Language & Tech: Almost no English is spoken. We recommend having a translation app and all your travel documents printed in Japanese if possible. The hospitality is warm and communicative through smiles and gestures.
• Cash Only: Sanka Onsen is a traditional rural lodge. Credit cards are not accepted. Bring sufficient cash for your room and bathing fees. The nearest ATM is in Teshikaga town (20 mins away).
• Connectivity: Mobile signal is stable, but free Wi-Fi is only available in the lobby area. It is the perfect place to disconnect from the internet.

2025-2026 Latest Updates

In 2025, Sanka Onsen launched a “Botanical Bathing” program, where guests receive a guide to the seasonal flowers in the garden to identify while soaking. For the 2026 season, the inn is planning to introduce “Lakeside Breakfast Hampers,” allowing guests to take their morning meal to the shore of Lake Kussharo for a private picnic.

Safety & Manners

In the onsen, always rinse your body thoroughly before entering the tub. Because the water is clear and the garden is visible, do not bring towels into the water. In the inn, walk quietly in the corridors as the walls are traditional and sound carries. Finally, be “Bear Aware”—carry a bear bell if you are exploring the forest trails behind the inn at dawn or dusk. Respect the silence of the garden; it is the soul of Sanka Onsen.