Lake Shikotsu was formed by a volcanic eruption around 44,000 years ago. Today it’s one of the clearest lakes in Japan, and the spectacular rock formations are known locally as the “underwater Grand Canyon” can even be seen from the surface. Head out on the water in a clear-bottom kayak and view this magnificent underwater environment right under your feet. Following the spring thaw, the visible depth of the lake increases to an incredible 30 meters. Later on, in summer, beautiful flora and fauna species begin to show up under the surface, including the ethereal white flowers of the chitose baikamo plant, curly-leaf pondweed, and schools of up to 1,000 tribolodon sachalinensis, a species of fish endemic to Japan.