Ichinokurasawa Gorge was added to Your Favorites!
Joshin’etsukogen NP, Gunma
Claim this place to tell your story your way.
The low ridge at the gorge mouth is a moraine left by an Ice Age glacier. A nearby boulder matches rock near the summit, evidence that ice carried material far down the mountain to this surprisingly low spot.
In June 1958, climbers including Tatsuo Matsumoto made the first ascent of Ichinokurasawa’s Cup-shaped Main Wall using newly developed bolts. Their breakthrough helped open a new era of bolted aid climbing in Japan.
A 1977 study measured 9,000 m³ of snow still in Ichinokurasawa on Dec 10, after a cool melt season despite near-average winter snowfall. Historical records also note complete melt-outs in 1893, 1948, 1973 and 1976.
Mossy stone walls along today’s approach survive from a road built over Shimizu Pass in 1885. Landslides and avalanches made the route impassable by 1888; parts of its old line now continue as mountain trails.
These cliffs are more than climbers’ territory: Japan’s environment ministry identifies Ichinokurasawa as a breeding site for Asian house martins (Iwa-tsubame). White-throated needletails and Pacific swifts are also seen here.
In local dialect, “kura” means a rock or cliff. “Ichinokura” names this as the Tanigawa range’s foremost crag—a place-name that describes the mighty rock face rather than a storehouse.
The narrow, gutter-like grooves on the wall are avalanche chutes. Fieldwork at Ichinokurasawa found avalanches carry weathered rock fragments downhill, while sliding snow and grit leave fine scratches on the bedrock.
