富士吉田市外ニヶ村恩賜県有財産保護組合の紹介

Mt. Fuji’s elegant beauty is a symbol of Japan not only for the people in Japan, but for people throughout the world. It is said that the mountain has been known as a sacred mountain for centuries ever since Priest Fuji opened access to the mountain. This started the tradition of the Fujisan Shugen-do (a spiritual ascetic tradition practiced in the mountains, incorporating both Shinto and Buddhist concepts). Mt. Fuji continued to be a spiritual center in many different belief systems, which eventually lead to the establishment of a community of pilgrims called "Fuji-ko". Women were forbidden to enter the mountain until the end of the Edo period (1603-1867).

There are many sites where people visit around the base of Mt. Fuji. During the summer season, many come to climb the mountain. The Yoshida Trailhead serves as a gateway to the mountain from Yamanashi prefecture, and it is crounded with climbers each year. The mountain summit temperature averages 6°C, ranging from 0°C to 10°C, even during hottest days in August. This can be characterized as being a tundra climate.

The Birth of Mt. Fuji

Mt. Fuji is believed to have assumed its present shape approximately 10,000 years ago. The land had been actively erupting in the region for tens of thousands of years. Volcanic ash and lava accumulated over a long period of time, forming mountains that rose to over 3,000 m above sea level. A major eruption approximately 11,000 years ago resulted in massive lava flows. After the lava cooled and hardened, it is inferred that weathering from wind and rain caused the central portion of the volcano to collapse, truncating the apex of the conical shape, leaving the form we are so familiar with today.

History of Major Eruptions

A major eruption called the Enryaku Eruption occurred around 800 AD. The eruption that led to the Aokigahara lava flow took place during the Great Jogan Eruption in 864 AD. The most recent eruption of Mt. Fuji was the Great Hoei Eruption in 1707 AD, where fumes rose to the stratosphere, leaving the city of Edo (present-day Tokyo) with about a 4cm layer of volcanic ash. It was during this last eruption that Mt. Hoei was formed on the southwestern slope of Mt. Fuji. Volcanic earthquakes and venting activities have been carefully surveyed since then.

Because Mt. Fuji has not erupted in the 300 years since the Great Hoei Eruption, recent elementary school textbooks have taught children that Mt. Fuji is a dormant volcano. However, significant signs of activity continue to be observed, and with the Japan Meteorological Agency removing Mt. Fuji from the list of dormant volcanoes, the mountain is, today, officially classified as an active volcano.

Shape of Mt. Fuji

Mt. Fuji’s exquisite conical silhouette is characteristic of a stratovolcano or composite volcano that has been built up through repeated eruptions over tens of thousands of years. Other stratovolcanoes in Japan include Yatsugatake and Mt. Akagi. These, however, are not considered as beautifully conic as Mt. Fuji. The elegance of Mt. Fuji was miraculously created as a result of many different geological factors coming together, such as the way it has erupted, the stratigraphy, and the magma zone.

To ensure the survival of the beautiful Mt. Fuji into the future, Yamanashi and Shizuoka prefectures have joined forces in an effort to make Mt. Fuji classified as a World Heritage Site.