Onneto Hot Spring Waterfall
Walk Beside Steaming Black Cliffs and Witness the Earth in Motion
Hidden within the forests surrounding the mystical Lake Onneto, this spectacular waterfall offers one of Hokkaido’s most extraordinary natural sights.
A gentle 1.5-kilometer walk through lush Akaezomatsu spruce forest leads to Onneto Hot Spring Waterfall, where steaming mineral water cascades quietly over dark volcanic rock. Once a secluded hot spring retreat, the area is now protected for its rare geological significance. The waterfall’s black rock surface is shaped by a unique natural process. Manganese-rich hot spring water, flowing at around 35°C, is oxidized by microorganisms in the water. Over time, these minerals accumulate to form rare manganese deposits across the cliff face.
What makes this site exceptional is that manganese deposits—normally formed deep on the ocean floor—can be observed here on land at such a large scale. Designated a National Natural Monument, it is considered one of the world’s rarest geological landscapes. Today, bathing is prohibited to protect this fragile environment and the ongoing formation of manganese oxides. Surrounded by quiet forest, drifting steam, and blackened stone, visitors can witness the powerful forces shaping the Earth.
- * Please note that the text shown on this page includes machine translations.
- Nearest airports
General Information
- Postal code
- 〒089-3963
- Address
- 北海道足寄町上螺湾
- Telephone Number
- 0156-25-6131（Ashoro Tourism Association）
- Closed
- Closed in winter
- Car Park
- 50 spaces, free
- Directions
- ●By car: About 50 minutes from Doto Expwy Ashoro IC
●By car: About 100 minutes from JR Kushiro Station - Website
* Information on facilities is subject to change. Please check each official website for the latest information.
