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Chichibu-Tama-Kai NP, Tokyo
Claim this place to tell your story your way.
Even in early March, with snow still on the ground, Nagare-tagogaeru frogs gather in this stream to breed—sometimes more than 100. Males occasionally clasp a yamame trout by mistake.
A 2019 stream survey found larvae of the mukashi-tombo, Japan’s relict “living fossil” dragonfly. They can spend about 8 years underwater before emerging—an astonishingly long childhood beneath these rocks.
A 2019 biological survey rated Rock Garden’s stream 9 on Japan’s aquatic-life water-quality scale, where 7.5–10 means “very clean.” The same water has long served mountain residents as drinking water.
At the upper end of Rock Garden, Ayahiro Falls has long been used for Musashi-Mitake Shrine’s waterfall purification rites. That spiritual role gave it another name: “Misogi no Taki,” or “Purification Falls.”
Yamame trout here can seem remarkably unbothered by hikers. A Mitake Visitor Center interpreter once floated a leaf into the stream, and a fish snapped at it—mistaking the falling leaf for an insect.
From early to late August, yellow Tamagawa-hototogisu—a kind of toad lily—blooms among Rock Garden’s streamside rocks. Tokyo’s nature guide specifically lists this gorge as a place to find it.
Near Rock Garden, Tengu Rock is said to resemble a long-nosed tengu, a guardian of mountains and forests in Japanese folklore. Look up from the trail: a small bronze tengu statue sits on the rock’s summit.
The gorge is natural, but its public landscape has a 1930s history: Tokyo Prefecture began a scenic-garden project on Mitake in 1935. The surrounding Okumitake Scenic Area became a Tokyo-designated scenic site in 2000.
