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Towada-Hachimantai NP, Aomori
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Japanese horse-chestnut trees line the stream, and local beekeepers gather nectar from their blossoms around mid-June for Towada honey. Its reddish color and gently tangy taste make it a local specialty.
At 7 m high and 20 m wide, Choshi Otaki was a natural fish barrier to Lake Towada. A fish ladder was added in 1894; Towada’s famous kokanee, or himemasu, arrived as eggs from Hokkaido in 1902.
Oirase is Lake Towada’s overflow route: as the lake rose, its water eroded the volcanic rim until it broke through, then carved the gorge visitors follow today.
Oirase became Japan’s 19th “Precious Moss Forest” site in 2013. More than 300 moss species have been recorded here, growing on stream-washed stones, tree trunks, fallen wood and even bridge rails.
Ishigedo means “stone hut” in local dialect: a huge slab propped by a katsura tree looks like a rocky shelter. Local legend says the bandit Onimatsu once used this natural hideaway.
The river looks wholly wild, but its flow is partly managed: Lake Towada water is diverted for hydropower, and a gate at Nenokuchi controls releases with the gorge’s scenery in mind.
Travel writer Ōmachi Keigetsu first visited in 1908 and published an account of the journey in the magazine Taiyō. His writing helped make the then little-known Towada and Oirase famous across Japan.
Listen for the dipper, a familiar Oirase stream bird. It dives for aquatic insects and can walk along the riverbed underwater—a remarkable way for a bird to forage in fast-flowing water.
Some Oirase boulders are large enough to support miniature woody plant communities. A prefectural vegetation survey records trees and shrubs growing on streambed rocks larger than about 5 m².
The route’s predecessor was a forestry road, completed between Yakeyama and Nenokuchi in 1903. Work on the modern walking trail began in 1961 and continued until its completion in 1975.
Making Towada and Oirase a national park was not a quick decision: advocates for protection faced competing plans to use the lake’s water for power and irrigation. The park was designated in 1936, after years of debate.
