Mount Tarumae, Active stratovolcano in Shikotsu-Toya National Park, Japan

Mount Tarumae is an active stratovolcano in Shikotsu-Toya National Park in Japan that reaches 1,041 meters above sea level. The crater contains a lava dome formation with steam vents, and its position offers views toward both Lake Shikotsu and the Pacific coast.

Large eruptions in the 17th and 18th centuries formed the current cone shape and crater of the volcano, with the 1739 event being particularly extensive. A phreatic eruption in 1982 marked the most recent documented outburst from the mountain.

The name derives from Ainu taor-oma-i, "high place on the river bank", likely naming the Tarumae River that runs down the mountain's south side rather than the peak itself. An 1807 screen painting by Hata Mokumaru records the mountain's own Ainu name, Ofuy-nupuri, "burning mountain". Locals still say "Tarumai-san", and the alpine flower Iwabukuro is also called Tarumai-so here.

The starting point for the climb lies at a seventh station parking lot, from which a steep trail leads to the crater in about an hour. Sturdy footwear and enough drinking water are necessary for the hike, as the path rises over loose volcanic rock.

Koke-no-domon, at the northwestern foot, is not a lava tunnel but a moss-covered rock face. A former trail from Lake Shikotsu passed between the mossy rocks; it was closed to protect the moss and because of rockfall, and part of it became a viewing path and platform. Heavy rain in September 2014 collapsed part of the grotto and the path, which has since been closed.