Lake Mashū

Crater lake in Akan Mashu National Park, Hokkaido island, Japan

Lake Mashū (摩周湖, Mashū-ko) (Ainu: Kamuy-to) is an endorheic crater lake formed in the caldera of a potentially active volcano. It is located in Akan Mashu National Park on the island of Hokkaido, Japan. It has been called the clearest lake in the world.

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