Mount Aso is actually a volcanic complex that includes about fifteen other volcanic peaks as well as Aso, with a population of about 100,000 inhabitants. Its caldera, a vast plateau made by previous eruptions, measures 25 km from north to south and 17 km from east to west.
We count 5 main domes:
- Naka-dake: 1,506m, the most active and popular
- Taka-dake: the highest with at 1,592m and with a crater 600m in diameter
- Neko-dake: 1,408m, considered the oldest one
- Kijima-dake: 1,321m
- Eboshi-dake: 1,337m
The caldera was formed between 300,000 and 80,000 years ago during the four eruptions, called Aso 1, 2, 3 and 4. The whole complex has experienced more than 160 eruption events since the year 533, as confirmed by documents from that time. One recent eruption happened on September 14th, 2015. On October 8th, 2016, volcanologists witnessed an explosive eruption on a peak that had been in a sleep status since 1980.
Despite some dangers, mostly due to sulfur gas, Mount Aso remains accessible to tourists. In the 1990s, concrete bunkers were built around the crater of Naka-dake to allow hikers to shelter in case of eruption. In that case, access would be forbidden to the public up to one kilometer around the volcano, and the cable car giving access to it would close. Before scheduling a hike there, it is wise to check for official information related to the volcano’s status.
Please note that the serial earthquakes that impacted Kumamoto in April 2016 still affect the whole site. Naka-dake and its blue lake were closed for a time but opened again in 2018. It is advised to choose hiking trails on other peaks, such as Taka-dake, which offers a magnificent view of the surrounding landscape. Less sporty tourists will have an easier climb at the lower Kishima-dake mount.
Another main attraction, the vast grass-covered plain Kusasenri-ga-hama welcomes cows and horses who come here to graze. Horseback riding is possible, but not in winter. On the opposite side is the Aso Volcano Museum and research center, with two real-time cameras filming inside the crater.
From this high plateau, we can admire one of the most emblematic landscapes of the area: Komezuka, the all-green symmetrical crater, which can be photographed from the two roads crossing the caldera. For a comprehensive visit, we recommend stopping at one of the hot springs, such as Akamisu, Aso-Uchinomaki, Jigoku, Tarutama or Yunotani-Aso.
How to get to Mount Aso
By bus -- ~2h by Kyushu Odan or Yamabiko bus service to Aso / Beppu (¥1,500 / ~US$ 13.90 or covered by the Sun Q Pass). From Aso Station, 40 minutes by bus, Aso Crater Line to "Asosan Nishi-Eki" stop to access the crater Naka-dake when it's opened.
By car -- ~1h from Kumamoto Station
By train -- ~1h10 by rapid train on the JR Hohi Line (¥2,240 / ~US$ 20.80 or covered by the Japan Rail Pass) - Suspended since December 2016!
Location unreachable with the JR Pass
Get there with a rental car
Aso Volcano Museum:
- Adults: ¥880 / ~US$ 8.20
- Seniors: ¥700 / ~US$ 6.50
- Children: ¥440 / ~US$ 4.10
Disabled people: ¥550 / ~US$ 5.10 (adults) and ¥270 / ~US$ 2.50 (children)
Get your Japanese Yens free of charge
Aso Volcano Museum: open daily from 9 a.m. to 5 p.m. (last admission until 4:30 p.m.)
Best season in summer
How long / when to visit
Allow one to two days
Accomodation in Mount Aso
Following the April 2016 earthquake in Kumamoto: traffic on roads and rail is still disturbed + Naka-dake was re-opened on February 28, 2018, but its cable car is still closed.
Due to intense volcanic activity, the Naka-dake crater is regularly closed to public. Check current restrictions here.