Koganeyu Onsen: Sapporo’s Hidden “Back Parlor” and the Legend of the Sacred Katsura Tree
Nestled in the lush Toyohira River valley just 40 minutes from the heart of Sapporo, Koganeyu Onsen is a destination for those seeking tranquility without the long journey. Known as the “Inner Retreat” or “Back Parlor” of the city, this hot spring enclave is defined by its intimate scale and its deep connection to the history of Hokkaido’s development. While its neighbor Jozankei is larger and more bustling, Koganeyu offers a meditative, “slow-life” experience. The area is famous for its simple sulfur springs and the magnificent 700-year-old Katsura tree, which stands as a silent witness to the region’s origins. Whether you are seeking a quiet soak in a cypress-scented bath after exploring the nearby Ainu Culture Center or watching the autumn moon reflect in the river, Koganeyu provides a refined escape that harmonizes urban convenience with the profound beauty of nature.
Key Information
| Address | 〒061-2274 北海道札幌市南区小金湯 / Koganeyu, Minami-ku, Sapporo City, Hokkaido |
| Google Maps | View on Google Maps |
| Spring Quality | Simple Sulfur Springs (Weakly Alkaline) |
| Benefits | Neuralgia, joint pain, chronic fatigue, skin beautification, and relief from sensitivity to cold |
| Access | 60 min by “Jotetsu Bus” from JR Sapporo Station; 40 min by car from central Sapporo |
| Number of Ryokans | Centered around two primary historic inns: “Yumoto Koganeyu” and “Matsunoyu” |
| Day-trip Bathing | Highly popular at both main facilities; Adult fee approx. 800-950 yen |
The Healing Waters: Simple Sulfur and “Transparent Rejuvenation” Science
The waters of Koganeyu gush from the subterranean volcanic bedrock of the Toyohira valley. Scientifically, these are weakly alkaline simple sulfur springs, noted for their gentle mineral balance and clear transparency. The low alkalinity acts as a natural skin conditioner, gently softening the skin’s surface and removing old keratin—earning it the nickname “Bihada-no-yu” (Beautiful Skin Bath). The sulfur content, while subtle, provides an antioxidant effect that promotes blood circulation and skin metabolism. Unlike the intense red or milky baths of other regions, Koganeyu’s water is “smooth” and less irritating, making it suitable for long, restorative soaks that help balance the autonomic nervous system and relieve the stresses of modern city life.
Top Recommended Ryokans & Stays
- Yumoto Koganeyu (Historic/Scale): A refined facility that perfectly blends tradition with modern comfort. It features a spacious open-air bath surrounded by a traditional Japanese garden and a restaurant known for its high-quality Hokkaido buffet. It is the best choice for those seeking a “Resort Ryokan” experience.
- Matsunoyu (Heritage/View): Founded in 1956, this inn emphasizes a rustic, cozy atmosphere. Its outdoor bath offers a direct, dramatic view of the Toyohira River and the surrounding mountains. It is highly regarded for its quiet, nostalgic ambiance and its “at-home” Japanese hospitality.
- Sapporo Pirka Kotan Lodges (Cultural Experience): Located adjacent to the Ainu Culture Center, these provide a unique stay for those wanting to immerse themselves in indigenous traditions before visiting the onsen.
- Jozankei Tsuruga Resort Spa (Nearby Luxury): For those wanting five-star resort comfort, staying in nearby Jozankei allows for a short day-trip to Koganeyu’s hidden springs while enjoying full spa amenities at night.
Must-Visit Public Baths (Soto-yu)
Koganeyu is a compact enclave where both **Yumoto Koganeyu** and **Matsunoyu** act as the primary “Soto-yu” for the region. For around 900 yen, visitors can access the large indoor mineral pools and the iconic outdoor baths. For a unique experience, don’t miss the **Koganeyu Sakura no Mori Park**, which features a “Forest Footbath” during the spring and summer months (best in May during cherry blossom season). Note: Both main inns are very popular with locals on weekends; arriving before 11:00 AM is recommended for a more peaceful soak.
Walking Guide & Scenic Spots
Exploration on foot is essential to appreciate the spiritual atmosphere of the valley. Start with the **700-year-old Katsura Tree**; standing on the grounds of the onsen area, this tree is a designated natural monument and the site of the original hot spring discovery. Next, visit **Sapporo Pirka Kotan (Ainu Culture Promotion Center)**; this world-class facility features a reconstructed village (Kotan) and hands-on craft workshops. For nature lovers, walk the **Toyohira River Promenade**; in autumn (mid-October), the valley walls are painted in vibrant red and gold maples. For a wider view, drive to the nearby **Hakkenzan Winery** to see the vineyards at the base of the sharp-peaked Mount Hakken.
Local Gastronomy & Souvenirs
Koganeyu is a gateway to the agriculture of the Minami-ku district. You must try the **Koganeyu Soba**, made with locally harvested buckwheat and mineral spring water. Another specialty is **Sapporo Fruits**; the area is famous for its orchards—try the fresh apples or original apple cider at the winery. For souvenirs, look for **Ainu Handicrafts** (embroidery and woodwork) from the Pirka Kotan gift shop and hand-crafted **Katsura Tree Charms**. Don’t miss the original **Koganeyu Onsen Manju**, steamed using the heat of the local springs.
Cultural & Historical Context
The name “Koganeyu” translates to “Golden Water,” a reference to the rich yellow sulfur deposits originally found in the riverbed. The area’s modern history began in the late 19th century when the monk Miizumi Jozan (the founder of Jozankei) was reportedly guided to the springs by the spirit of the ancient Katsura tree. Historically, Koganeyu served as a vital resting point for pioneers who traveled between Sapporo and the southern coast. Today, it is a center for **Ainu Cultural Preservation**, with the Pirka Kotan facility serving as a bridge between the indigenous wisdom of the past and the sustainable tourism of the future.
Practical Travel Tips
Transportation: The “Jotetsu Bus” (Routes 7 and 8) runs frequently from Sapporo Station; look for the “Kappa Liner” for a faster, direct service (reservation required). Connectivity: Unlike the remote mountains, Koganeyu has **excellent mobile signal and free Wi-Fi** at the main inns. Seasonality: Late April for cherry blossoms at Sakura no Mori and late October for the best canyon foliage are the peak times to visit. Tattoos: Both Yumoto Koganeyu and Matsunoyu are relatively traditional; guests with large tattoos should confirm the policy at the front desk or book a stay with a private bath option.
2025-2026 Latest Updates
In February 2026, Koganeyu will host its first **”Valley Candle Night,”** where thousands of candles will illuminate the path between the ryokans and the Pirka Kotan center. Additionally, the **Yumoto Koganeyu** inn has recently completed an upgrade to its “Snow-viewing Terrace” for the 2025-2026 winter season, featuring heated outdoor loungers for international guests.
Safety & Manners
In the onsen, always rinse thoroughly before entering the communal tub and maintain a quiet, respectful tone to honor the meditative atmosphere. When visiting the Ainu village, please remember that it is a sacred space; ask for permission before taking close-up photos of residents. Finally, Koganeyu is a peaceful valley; please maintain a quiet tone during your evening walks and take all trash back to your hotel to help keep the Toyohira River the cleanest water source for Sapporo.
