There is no bus to Lake Kuttarako, so you have to take a taxi or rent a car. Lake Kuttarako has not been developed as tourism yet. That’s why there are few people to go there.
Lake Kuttara is a circular caldera lake, which is a part of Shikotsu-Toya National Park. The lake has very clear water which is recognized as the best water quality all over Japan. Its transparency is ranked second next to Lake Mashu(摩周湖).
There is no river which is out and into the lake, also few species. But since 1909,Sockeye salmon have been introduced to the lake and cultivated. From the middle of May to the end of July, you can fish with a rental boat.