The mountainous region is surrounded by the lower plains and hills of the Hokkaidō deciduous forests ecoregion. Central to the region is the Daisetsuzan Volcanic Group, the location of Daisetsuzan National Park, the largest national park in Japan. The highest mountain on the island, and in the region, is Asahi-dake with an elevation of . Above the conifer line, alpine conditions support thickets of Stone pine (Pinus pumila)