Lake Kussharo, with a circumference of 57 km and an area of 79.3 km2, is the largest caldera lake in Japan.
It was formed about 30,000 years ago inside the Kussharo Caldera, which is the largest caldera in Japan, measuring about 26 km east to west and 20 km north to south.
Incidentally, the word “Kussharo” originates from the aboriginal Ainu language meaning “throat,” the outlet of a lake or swamp.
Despite its massive size, Lake Kussahro’s water is 80% spring water, which explains why it’s so pristin.
On a clear day, the water turns a beautiful cobalt blue.
Many hot springs flow out from the lakeside, and the lake is also popular as a resort area for camping, yachting, fishing, and other activities.
In the 1970s, the discovery of a mysterious dinosaur-like creature called “Kusshi” caused quite a stir.