Kotan Onsen: Where Hot Spring Meets Nature

These all-natural open-air hot spring baths sit at the heart of the Lake Kussharo region and are completely free to take a dip in. Despite being free, the baths are regularly cleaned and maintained by a local organization to ensure a sanitary bathing space. The surface of the bath appears like it is level with the lake, and gives visitors the illusion that the hot spring and the lake are one and the same.  Swans often swim in the lake during the winter. Guests can gaze out at the gorgeous white birds during a soak and feel as though they are sharing a bath. The facility has separate changing rooms for both men and women, but the baths themselves are mixed gender, aside from one large dividing rock. It is perfectly acceptable to wear a bathing suit or use a towel if that feels more comfortable.