Mt. Daisen Landscape
As the tallest mountain in the Chūgoku region, Mt. Daisen dominates the area where Tottori, Shimane, and Okayama prefectures converge. Its highest peak stands 1,729 meters above sea level, a striking rise in elevation from the nearby coast. Covering a territory of 120 cubic kilometers, Mt. Daisen has several aspects that change depending on your viewpoint. Seen from the west, Daisen closely resembles the conical shape of Mt. Fuji, but from the north its slopes stretch out into a 2-kilometer-long cliff wall.
Mt. Daisen was gradually formed by a series of volcanic eruptions that began around one million years ago. Two main phases are responsible for its current appearance: in the first phase, a series of eruptions occurring between 600,000 and 400,000 years ago gradually deposited lava and ash that formed the base of Daisen and of nearby Mt. Senjō (615 m). The second phase, which began around 400,000 years ago, produced a lava dome that caps the mountain and forms the peaks of Misen (1,709 m) and Sankohō (1,516 m). Though now dormant, Daisen has a history of impressive volcanic activity. One eruption around 50,000 years ago spewed ash as far as Niigata Prefecture, some 450 kilometers to the northeast.
Mt. Daisen is composed primarily of two kinds of volcanic rock—andesite and dacite—and its slopes are extremely brittle. A portion of the trail to Kengamine (1,729 m), the highest peak, collapsed in 1982, and since then the trail has been closed due to the danger of rockslides.
