Lake Akan

Lake Akan is a volcanic caldera lake located in eastern Hokkaido's Akan Mashu National Park, approximately 90 kilometers from Kushiro Airport. The lake sits at an elevation of 420 meters and covers an area of roughly 13 square kilometers, with a maximum depth of 45 meters. Its formation dates back thousands of years to volcanic activity that created the distinctive landscape of Mount Oakan and Mount Meakan flanking the water.

The lake gained international scientific attention for its population of marimo, rare spherical green algae that grow naturally in only a few locations worldwide. These algae balls, which can take decades to form their distinctive round shape, were designated a Special Natural Monument of Japan in 1921 and have become the lake's most iconic feature. The Ainu people, the indigenous inhabitants of Hokkaido, have long revered the lake and its surroundings, establishing settlements along its shores centuries before Japanese colonization.

The thermal resort town of Akankohan on the lake's southern shore serves as the primary base for visitors. Here you can experience traditional Ainu culture at the Ainu Kotan village, where artisans demonstrate wood carving, embroidery, and traditional dance performances.

The Marimo Exhibition and Observation Center on Churui Island, accessible by sightseeing boat, provides close-up views of the protected algae and explains their ecological importance. Winter transforms the lake into a venue for ice fishing wakasagi (pond smelt) and the annual Lake Akan Ice Festival, while summer offers hiking trails up the surrounding volcanic peaks.

Transportation to Lake Akan requires either private vehicle or bus service. Regular buses operate from Kushiro Station with a journey time of approximately two hours, while seasonal services connect from Kushiro Airport in roughly 70 minutes. The lake area itself has no admission fee, though individual attractions charge separate entry fees.