It is located in Akan National Park and is a Ramsar Site.

[2][3] Volcanic activity formed the lake some 6,000 years ago, when a lava dam was formed.

Pollution from local hotspring resorts has decreased the transparency to 3–4 meters.

[4] The lake is famous for its marimo (Aegagropila linnaei), aggregations of algae that form into spherical shapes 2–30 cm in diameter.

Other flora of the lake include the following:[4] Kokanee salmon (Oncorhynchus nerka) are native to Lake Akan.