Mount Aso, located in Aso Kujū National Park, is the largest active volcano in Japan, and is among the largest in the world, with one of the largest calderas (25km north-south and 18km east-west), which contains the city of of Aso as well as Aso Takamori-cho and South Aso-mura. The central cone group consists of five peaks: Mt. Neko, Mt. Taka (the highest, with 1592m), Mt. Naka (also called Nakadake or Naka-Dake), Mt. Eboshi, and Mt. Kishima. Only the northernmost crater has been active for the last 70 years, last time in 2011. Viewpoints from the somma overlooking the caldera are perched upon lava formed before the volcanic activity which created the present caldera. Ejecta from the huge caldera eruption 90,800 years ago covers more than 600 km³ and roughly equals the volume of Mt. Fuji; it is presumed that the pyroclastic flow plateau covered half of the island of Kyūshū.
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