Mount Aso or Aso Volcano is the largest active volcano in Japan and among the largest in the world. Common use relates often only to the somma volcano in the centre of Aso Caldera. It stands in Aso Kujū National Park in Kumamoto Prefecture, on the island of Kyushu. Its tallest peak, Takadake, is 1,592 meters above sea level. Mount Aso is in a fairly large caldera with a circumference of around 120 km, although sources vary on the exact distance.