Mount Aso (阿蘇山 Aso-san) is the largest active volcano in Japan, and is among the largest in the world.
It stands in Aso Kujū National Park in Kumamoto Prefecture, on the island of Kyūshū.
Its peak is 1592 m above sea level. Aso has one of the largest caldera in the world (25 km north-south and 18 km east-west). The caldera has a circumference of around 120 km (75 mi), although sources vary on the exact distance. …
Aso is one of the best hikes in Japan. So — as expected — I wasn’t able to hike it.
It seemed we were well organized for this one, up early and arriving by rent-a-car before the tour buses.
Yet the Buddha said we could not continue up the mountain. Trails were closed due to Sulphur Dioxide emissions.
I briefly considered going off trail. But the stink really was choking.
… And, in fact, I understand the trails and ropeway are often closed for this reason.
More bad luck for me on this trip.
Here’s the scoop on how to actually walk that destination – Hiking in Japan blog – Mt. Aso (阿蘇山）
The most iconic image is this unusual feature, the ‘rice mound’.
That’s from a CNN article – Mount Aso and me: How I risked death on a Japanese volcano
See photos of Aso on Flickr.