is located in the Shikotsu-Toya National Park

Shikotsu-Toya National Park

is a national park in the central part of the island of Hokkaidō, Japan. Named after the volcanic caldera lakes of Lake Shikotsu and Lake Tōya, it has a total area of 993.02 square kilometers...

 in Hokkaidō

Hokkaido

, formerly known as Ezo, Yezo, Yeso, or Yesso, is Japan's second largest island; it is also the largest and northernmost of Japan's 47 prefectural-level subdivisions. The Tsugaru Strait separates Hokkaido from Honshu, although the two islands are connected by the underwater railway Seikan Tunnel...

, Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

. It is located near both Tomakomai and Chitose

Chitose, Hokkaido

-Economy:China Airlines operates its Sapporo office on the third floor of the airport building.The airline Hokkaido Air System was at one time headquartered at the New Chitose Airport in Chitose...

 towns and can be seen clearly from both. It is on the shores of Lake Shikotsu

Lake Shikotsu

is a caldera lake in Chitose, Hokkaidō, Japan. It is a part of the Shikotsu-Toya National Park.- Geography :Lake Shikotsu is located in the south-west part of Hokkaidō. It has an average depth of and a maximum depth of , making it the second deepest lake in Japan, after Lake Tazawa...

, a caldera

Caldera

A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption, such as the one at Yellowstone National Park in the US. They are sometimes confused with volcanic craters...

 lake. Tarumae is a 1,041 metre active andesitic

Andesite

Andesite is an extrusive igneous, volcanic rock, of intermediate composition, with aphanitic to porphyritic texture. In a general sense, it is the intermediate type between basalt and dacite. The mineral assemblage is typically dominated by plagioclase plus pyroxene and/or hornblende. Magnetite,...

 stratovolcano

Stratovolcano

A stratovolcano, also known as a composite volcano, is a tall, conical volcano built up by many layers of hardened lava, tephra, pumice, and volcanic ash. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile and periodic, explosive eruptions...

, with a lava dome

Lava dome

|250px|thumb|right|Image of the [[rhyolitic]] lava dome of [[Chaitén Volcano]] during its 2008–2009 eruption.In volcanology, a lava dome is a roughly circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano...

.

Eruptions

The most recent eruption, in 1982, was a phreatic eruption

Phreatic eruption

A phreatic eruption, also called a phreatic explosion or ultravulcanian eruption, occurs when rising magma makes contact with ground or surface water. The extreme temperature of the magma causes near-instantaneous evaporation to steam, resulting in an explosion of steam, water, ash, rock, and...

. Previous major eruptions have occurred in 1667, 1739, (plinian eruption

Plinian eruption

Plinian eruptions, also known as 'Vesuvian eruptions', are volcanic eruptions marked by their similarity to the eruption of Mount Vesuvius in AD 79 ....

 of VEI 5

Volcanic Explosivity Index

The Volcanic Explosivity Index was devised by Chris Newhall of the U.S. Geological Survey and Stephen Self at the University of Hawaii in 1982 to provide a relative measure of the explosiveness of volcanic eruptions....

) and 1909. The 1667 and 1739 eruptions were responsible for its present shape. Other eruptions were in 1919–21, 1923, 1926, 1933, 1936, 1944, 1951, 1953–55, and 1978.
Tarumae is an 'A' rank volcano — most likely to erupt in the relatively near future.

Hokkaido Natural Monument

Designated as a Hokkaido Natural Monument, it is popular as an easy climb for hikers who may start at the seventh station and then take an hour to reach the crater.

At the foot of Tarumae on the north-west side one can find an impressive moss-covered cavern

Cave

A cave or cavern is a natural underground space large enough for a human to enter. The term applies to natural cavities some part of which is in total darkness. The word cave also includes smaller spaces like rock shelters, sea caves, and grottos.Speleology is the science of exploration and study...

(Koke-no-domon).