Onneto, a beautiful lake with a circumference of 2.5 km, is located at the westernmost tip of Akan Mashu National Park in Ashoro Town, at the foot of Mt. This mysterious lake changes its color from clear blue to emerald green to dark blue depending on the season, weather, and viewing angle.

Onneto, a beautiful lake with a circumference of 2.5 km, is located at the westernmost tip of Akan Mashu National Park in Ashoro Town, at the foot of Mt. This mysterious lake changes its color from clear blue to emerald green to dark blue depending on the season, weather, and viewing angle.