Akaishi Onsen
赤石温泉
3.8 · 247 reviews · via Google
Akaishi Onsen
iron-sulfate · Chubu
Hotter than 11% of Japan springs (n=122).
More acidic than 7% of Japan springs (n=121).
Mineral profile
Bar width reflects listing order, not measured concentration.
Suitability
At a glance
Getting there
Moderate — a short ride from a station
Cost
High
Crowd level
Quiet
About this spring
Akaishi Onsen occupies a remote ryokan tucked into the Fujikawa valley of Yamanashi Prefecture, inside Minami Alps National Park. The water is an iron spring, and its minerals stain the stone soaking basins a warm ochre color. Peaks in the surrounding range climb past 3,000 meters. Just inside the forest stands a Himuro Shrine, tended beside a sugi cedar believed to be 1,200 years old.
Highlights
History
The Akaishi range goes by another name, the Southern Alps, and the iron-rich red stones of these mountains give both the range and the springs their character, the same mineral geology coloring the water that fills the baths today.
In earlier centuries the terrain was considered sacred and passed through only by ascetics and hunters. The inn stands next to a hidden waterfall in a valley that holds noticeably cooler temperatures than the lowland cities during summer, and that coolness drew visitors to the area even before the spring was formally developed.
Local guide
If you drive away from the flat Kofu Basin and follow the winding roads up into the mountains, the valley starts to close in around you. The air cools down quickly, and you will find yourself surrounded by the thick smell of cedar trees and wet river stones. Down at the bottom of the Togawa ravine, right where the cliffs rise up toward Mount Kushigata, you will find Akaishi Onsen. It is not a busy resort town at all. It is just a single, weathered wooden lodge that has been sitting by the rushing river since the late 1800s.
Most travelers come to Yamanashi hoping for a clear view of Mount Fuji, but the real treasures here are hidden right in the ground. The spring water at Akaishi is completely unique. When it first pumps out of the dark earth at a chilly twelve degrees, it looks as clear as tap water. However, it is packed full of natural iron and minerals. The moment it flows into the open air and mixes with oxygen, it changes color completely, turning into a thick, opaque reddish-brown that looks exactly like liquid clay.
Stepping into the heated bath here feels like experiencing a piece of old Japan. As you slide beneath the steaming, rust-colored surface, the stress of daily life goes away. The water has a sharp, sour metallic taste because of its high acidity, and you can feel a slight, clean tingle on your skin that locals say is excellent for soothing sore muscles and joints.
Because the water is so thick and muddy, you are completely hidden from view the moment you sit down in the pool. From the outdoor bath, you can listen to the loud roar of the Myouren waterfall just a short walk up the trail. If you look up through the rising steam, you can see the green forest canopy framing the quiet mountain sky. In the winter, the view is incredible because the heavy white snow on the rocks contrasts perfectly with the hot, deep-red water. It is a simple, unpolished place, but that is exactly what makes it such a great escape. If you are willing to make the drive up the mountain, this hidden bath will completely refresh you.
Mineral chemistry
Sulfate springs contain dissolved calcium, sodium, or magnesium sulfate. Calcium sulfate springs are traditionally associated with wound healing and post-surgical recovery.
Sodium sulfate springs can have a mild laxative effect in sensitive individuals — stay well hydrated.
Amenities
Getting there
From Shinjuku, take the JR Azusa limited express to Kofu Station, about 90 minutes. From Kofu, drive south on Route 52 along the Fujikawa River for about 40 minutes to the Hirabayashi area. A rental car from Kofu Station is strongly recommended as there is no convenient public transport to the inn.
Location & nearby
3243 Hirabayashi, Fujikawa, Minamikoma District, Yamanashi 400-0514
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Common questions
What is the water temperature at Akaishi Onsen?▾
The water temperature at Akaishi Onsen ranges up to 43°C (minimum around 12.6°C).
Is Akaishi Onsen free to visit?▾
Akaishi Onsen charges an entrance fee in JPY.
Is Akaishi Onsen a public or private bath?▾
Akaishi Onsen is a public bathing spring.
Are tattoos allowed at Akaishi Onsen?▾
Yes, Akaishi Onsen welcomes visitors with tattoos.
What is the nearest station to Akaishi Onsen?▾
The nearest station to Akaishi Onsen is Hirabayashi, about 1.9km away.