The Origin of Mt. Heisei Shinzan
This is the second observation point along Nita Pass. On a clear day, you should be able to see the peak of Mt. Heisei Shinzan (1,483 m) and look out over the city of Shimabara toward the Ariake Sea to the east.
Before November 1990, Heisei Shinzan did not exist. From this vantage point, you could see Mt. Fugen (1,359 m), which was then the tallest mountain on the Shimabara Peninsula, along with the shorter peaks to the east above the city of Shimabara. Volcanic activity began at the end of 1990 and over the next 5 years, lava domes would form and then collapse, sending destructive avalanches of hot gas, ash, and mud down the mountainside.
On June 3, 1991, the volcano erupted, causing a pyroclastic flow that killed 43 people and destroyed more than 2,000 homes. Debris from the eruption reached as far as the Ariake Sea. Pictures taken shortly after the event show a landscape devastated by the continual eruptions.
Nature, however, is resilient. This was far from, and these eruptions were not the first time the Unzen volcanoes had destroyed the community that lived at their base. By 1998, Heisei Shinzan had completely stabilized, and over the subsequent decades the mountain’s ecosystem has quickly recovered. Plants native to Unzen grow well in the volcanic soil, and grasses and shrubs were the first to return to the mountainside. Trees began to emerge within the first 10 years after the eruption.
For most, the Heisei Eruptions exist only in memory, and the devastation left behind is barely visible now that the landscape has leveled out and much of its flora has regrown.