Geological Sites

Area AreaKitanoyamaKitanoyama

There are more than 80 volcanic landforms on Izu Oshima Island that have been formed by eruptions that occurred on the side or base of the mountain (flank eruption) rather than from the crater at the top.

Mt. Atago, at the southern end of the Oshima Airport runway, is one of these volcanoes, as are Mt. Jinooka, Mt. Mitsumine and "Akahage". It is thought to have been created by an eruption some 3,500 years ago, before the formation of the caldera.

In the past, many trees were cut down all over Izu Oshima in order to make firewood and charcoal. However, because a shrine was set up on Mt. Atago, the mountain was protected and the trees were not cut down. This has led to the development of climax forest of Sudajii (Castanopsis sieboldii) and Tabunoki (Machilus thunbergii), forming a forest of giant trees.

Climax Forest

Atago Shrine

Location Information