Mt. Io
A Former Sulfur Mine and the Source of Kawayu Hot Spring.
Mt. Io (Atosanupuri), a once-prosperous active volcano due to sulfur mining, is the source of the hot spring waters of Kawayu Hot Spring. Countless fumaroles dot its brown mountainside, powerfully emitting white smoke containing sulfur. The air is thick with the scent of sulfur, and you can get very close to these fumaroles, allowing you to experience their dynamism firsthand.
Spreading at the foot of the mountain is a large colony of "Ezoisotsutsuji" (Hokkaido rhododendron), a species unique to Hokkaido. Growing in the harsh environment, it blooms beautiful pure white flowers from June to July. The "Tsutsujigahara Nature Exploration Trail" is maintained from the town of Kawayu Hot Spring to Mt. Io, and guided tours are also available.
- * Please note that the text shown on this page includes machine translations.
- Category
- With friends
- Shopping
- Solo trip
- Guys' trip
- Girls' trip
- Couple
- Family
- Travel style
- Souvenirs
- Animal habitats, plant habitats
- Mountain, ridge, plateau, marshland, canyon
- Natural scenery, spectacular views
- Travel Inspiration
- Enjoy spectacular views
- Best for a girls' trip
- Nearest airports
General Information
- Address
- 北海道川上郡弟子屈町硫黄山
- Telephone Number
- 015-483-3511（Iouzan Rest House）
- Car Park
- paid
- Directions
- ●By car: About 5 minutes from JR Kawayu Onsen Station
●By car: About 140 minutes from Doto Expwy Ashoro IC - Website
* Information on facilities is subject to change. Please check each official website for the latest information.
