Mount Aso is the largest volcano in Japan, and one of the largest in the world. An erruption that took place from 300,000 to 90,000 years ago created a huge caldera, 25km across north to south and 18km across east to west. Its circumference is estimated between 80 and 120km.
Although the caldera is now inhabitated by roughly 100,000 people spread over dozens of towns and villages, there are still active volcanoes toward the center of the caldera. There are five prominent mounts known as the Aso-gogaku (阿蘇五岳). These are Mt Taka-dake (高岳, 1592m), Mt Neko-dake (根子岳, 1408m), Mt Eboshi-dake (烏帽子岳, 1337m), Mt Nishima-dake (杵島岳, 1238m) and Mt Naka-dake (中岳, 1216m). The last one is still an active volcano and continuously emits smoke with occasional erruptions.
The main towns to access the Aso region are Aso on the Houhi line and Takamori on the Minami-Aso line.
How to get there
Trains from Kumamoto take 1h20min to Aso (￥1,080) and 1h30min to Takamori (￥1,190). Direct trains from Beppu take about 2h (￥3,440), but are limited to 4 per day.
Mount Aso is the largest volcano in Japan, and one of the largest in the world. An erruption that took place from 300,000 to 90,000 years ago created a huge caldera, 25km across north to south and 18km across east to west. Its circumference is estimated between 80 and 120km.