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Nikko NP, Tochigi
Claim this place to tell your story your way.
That colorful “island” below is Haccho-dejima, a wooded peninsula jutting into Lake Chuzenji. In Nikko’s public vote for favorite waterscapes, it ranked 4th—after Kegon Falls, Yudaki Falls, and the lake itself.
This panorama is a volcanic timeline: Mount Nantai’s eruptions about 25,000 years ago dammed river valleys, forming Lake Chuzenji and lakes around today’s Senjogahara. Pumice from a later eruption helped fill those lakes into marshland.
Lake Chuzenji’s autumn colors have an underwater chapter: himemasu, or landlocked sockeye salmon, swim up the Yukawa to spawn. Their red spawning colors inspired the local saying that the lake’s autumn begins underwater; the fish also became part of local food culture.
Lake Chuzenji was once believed to have no fish: its waterfall outlet blocked fish from swimming in, while sacred mountain rules prohibited stocking them. In 1873, local resident Hoshino Sadagoro released 2,200 char—the beginning of the lake’s fishing history.
The nearby Half-Moon Pass route once linked Ashio’s copper town with Chuzenji on foot. A local memoir recalls school groups touring the mine, staying overnight, then crossing the pass to Nikko; 5 teahouses served travelers along the way.
The Chuzenji Lake Skyline, the road leading toward this viewpoint, opened as a toll road in September 1972. It became free in September 1997, when its toll-collection period ended.
