Kunimi Onsen (国見温泉)

Introduction: The Mystical Emerald Sanctuary of the High Akita-Komagatake Border

Hidden deep within the primeval forests of the Ou Mountain range, at the very border of Iwate and Akita Prefectures, lies one of Japan’s most visually stunning hot springs: Kunimi Onsen (国見温泉). Perched at an elevation of 850 meters on the slopes of Mt. Akita-Komagatake, this hot spring is a geological anomaly world-famous for its Emerald Green water. This is the definition of a “Hitou” (hidden hot spring)—a place of absolute environmental purity and extreme mineral intensity. For the international traveler, Kunimi Onsen offers a profound encounter with the “Wild North.” It is a place to soak in vibrant green, sulfur-rich waters while watching the mist roll over the alpine tundra, breathe in high-oxygen mountain air, and experience the quiet, unpolished hospitality of a lodge that has served mountain climbers for generations. Whether you are a dedicated trekker aiming for the summits or a seeker of Japan’s rarest thermal colors, Kunimi is your spiritual destination.

Key Information Table

The Healing Waters: The “Emerald Elixir” of the High Peaks

The water at Kunimi Onsen is a hydro-geological masterpiece. It is a powerful Sulfur Spring characterized by its unique color.
The Green Phenomenon: Unlike standard milky sulfur springs, Kunimi’s water is a brilliant, translucent emerald green. Scientific theories suggest this color is a result of a specific interaction between sulfur, carbonate ions, and microscopic algae that thrive in the gentle temperature of the seepage.
The Sensation: This is a “Medicine Bath” (Kusuri-yu) in its most raw form. The sulfur content provides a powerful antiseptic effect, while the bicarbonate ions act as a natural cleanser. The high volume of natural flow (Gensen Kakenagashi) ensures that the color is always fresh and vigorous. The outdoor Rotenburo baths at Ishibacho Ryokan are built using local volcanic stones and offer a “zero-barrier” view of the surrounding mountain forest. Soaking here while being enveloped in the forest mist and the scent of sulfur is a spiritual experience of the highest order.

Top Recommended Stay: Kunimi Onsen Ishibacho Ryokan

• Kunimi Onsen Ishibacho Ryokan (国見温泉 石塚旅館): The primary lodge and the guardian of the emerald springs. This is a traditional mountain inn that prioritizes mineral purity and hiking logistics. The rooms are simple Japanese-style tatami spaces. The dining hall is famous for its **”Mountain Feast”**, featuring locally gathered wild vegetables (sansai), mountain trout, and Shizukuishi pork. Staying here allows for private access to the green baths at dawn, the best time for photography. Note: Guest rooms share communal onsen facilities; the experience is about returning to the basics of mountain life.
• Morinoshizuku (Nearby): Located slightly down the mountain, offering a more modern lodge feel with easy access to the hiking trails and the Kunimi springs.

Must-Visit Neighborhood Spots: Summits and Swamps

Mt. Akita-Komagatake: The trailhead starts directly from Kunimi Onsen. This is one of Japan’s top botanical mountains, famous for its rare alpine flora (like “Dicentra”) and active crater views.
Kunimi Pass: The historic border pass between old Nanbu and Akita. Walking through these ancient birch forests is a world-class forest bathing (Shinrin-yoku) experience.
Shizukuishi Pond (Nearby): A 20-minute drive down the mountain leads to beautiful lakeside parks and cycling paths.

Local Gastronomy: The Mountain Soul Food

Food at Kunimi is defined by its extreme altitude and the surrounding forest.
Wild Sansai (Mountain Vegetables): In spring, the lodge serves “Urui” and “Fuki” (butterbur) gathered from the Kunimi slopes.
River Fish: Mountain trout (Yamame) is caught nearby and salt-grilled over a charcoal hearth.
Vegetarian/Vegan Survival:
For Vegans: This area is a leader in Buckwheat and Soy. At the onsen lodge, you can request “Mountain Vegetable Soba”—specify “Katsuo-dashi nuki” (No fish dashi). The local “Kunimi Tofu” is exceptionally firm and flavorful. We recommend buying fresh seasonal fruit in central Shizukuishi before heading up to the heights.

Cultural & Historical Context

Kunimi Onsen was discovered by pioneers in the early 19th century who were mapping the mountain passes. For decades, it was a vital survival point for explorers and mountain priests who sought Misogi (purification) in the green waters. The name “Kunimi” means “Looking over the country,” referring to the panoramic views of both Iwate and Akita from the pass. Today, it remains a symbol of Iwate’s resilient “Hitou” (hidden spring) spirit—a place that preserves its unrefined, volcanic roots while welcoming the global climbing community.

Practical Travel Tips for International Visitors

• Winter Closure: **CRITICAL.** Kunimi Onsen is a seasonal facility. It is strictly closed in winter (typically from Nov 1 to mid-May) due to the complete closure of the mountain road. The building is literally buried in snow during this time.
• Tattoo Policy: As a wild, mountain-focused “Hitou,” Kunimi is generally very tolerant of tattoos. The focus here is on the healing quality of the water and the peace of the mountain. Full ink pieces are rarely an issue here if the guest is respectful.
• Connectivity: Zero mobile signal inside the valley. There is no Wi-Fi in the guest rooms. Prepare for an “offline” experience. Download your Mapcode and offline maps before leaving the town center.
• Cash Only: This is a traditional lodge in the mountains. Credit cards are not accepted for day-trip baths. Bring sufficient cash for your room and bathing fees. The nearest ATM is 20km away.

2025-2026 Latest Updates

In 2025, Kunimi Onsen launched the “Emerald Meditation Package,” providing guests with traditional Japanese incense and meditation mats to use on the terrace overlooking the forest. For the 2026 season, new “Panoramic Benches” are being installed on the ridge for better sunset photography of the “Green Water” landscape.

Safety & Manners

In the acidic sulfur baths, remove all silver jewelry as it will turn black instantly. Always rinse your body thoroughly before entering the communal tub. Because the water is opaque, walk carefully to find the submerged steps. Be “Bear Aware”—carry a bear bell if you are hiking the alpine trails alone. Finally, respect the quiet; many hikers stay here for the silence of the forest, so keep conversations in the communal baths to a respectful whisper.