Mount Tsubakuro is a 2,763-metre-high mountain in Azumino, Nagano Prefecture, Japan. It is situated in Japan's Hida Mountains in Nagano Prefecture. It was specified for Chūbu-Sangaku National Park on December 4, 1934. Granite forms the unique body with white sands and sharp rocks exposed at the top. Kassen One is a steep trail challengi…Mount Tsubakuro is a 2,763-metre-high mountain in Azumino, Nagano Prefecture, Japan. It is situated in Japan's Hida Mountains in Nagano Prefecture. It was specified for Chūbu-Sangaku National Park on December 4, 1934. Granite forms the unique body with white sands and sharp rocks exposed at the top. Kassen One is a steep trail challenging to climbers ascending from Nakabusa Hot Springs.