Kussharo Hot Sand (Sunayu) 屈斜路湖 砂湯
You only need to dig 10–30 cm into the sand on the shore and the hot spring water rises by itself, free of charge.
It lies on the shore of Lake Kussharo, inside the caldera of the same name. It is a natural geothermal phenomenon, not a facility: the hot spring water seeps up of its own accord beneath the sand of the shore. The name Sunayu literally means ‘sand hot water’.
Hokkaido
Sunayu (砂湯)