Shikotsu-Toya National Park

The three summit craters are known as "Father Cauldron", "Mother Cauldron" and "Little Cauldron". It is a 1 1/2mi/ 2km walk round the main crater.

To the south of Jokanzai-onsen the road crosses the Nakayama Pass (2,743ft/ 836m) and comes to the crystal clear Lake Toya, surrounded by mountains. In the middle of the almost exactly circular lake, which is 590ft/ 179m deep and does not freeze over even in severe winters, is the densely wooded island of Nakanoshima (or Oshima), surrounded by the much smaller islets of Kannon, Manju and Benten. On the southwest side of the lake is the popular health resort of Toyako-onsen, from which there are boats to Nakanoshima.

South on the lake are Mounts Usu and Showa-Shinzan, which can be climbed from Sobetsu on its southern shore. The active volcano of Showa-Shinzan (1,339ft/ 408m), which came into being only in 1944-45. Mount Usu is an active volcano, which formed Meiji-Shinzan ("new mountain of the Meiji period"), on its northern flank, in a great eruption in 1910 and Showa-Shinzan ("new mountain of the Showa period"), to the east in 1944-45. In the summit region are Great Usu (2,379ft/ 725m) to the east and Little Usu to the west, which together with the heights of the Byobuyama range enclose Lake Ginnuma.