Mount Aso
There are three VEI-7 volcanoes in Japan. These are the Aira Caldera, Kikai Caldera and Aso Caldera. These giant caldera are remnants of past eruptions. Mount Aso is the largest active volcano in Japan. 300,000 to 90,000 years ago there were four eruptions of Mount Aso which emitted huge amounts of volcanic ash that covered all of Kyushu and up to Yamaguchi Prefecture.