There are not many places in the world where a tourist ropeway leads up to a steaming and regularly active volcanic crater. Mt Aso in Kumamoto prefecture on Kyushu island is not only the largest active volcano in Japan, but is also one of the biggest in the world.
The area of Mt Aso consists of a series of peaks located in a massive caldera with a circumference of around 120 km. It stretches beyond the city of Aso, which will be your starting point should you travel by train. Many people give public transportation and the ropeway a miss and hike or bike up to the peaks. It’s well worth the effort, as you can stop by at horse ranches, cattle farms and quaint little villages on the twisted mountain pass.
While staying on the main mountain route, you get grand views of crystal clear lakes, cows grazing on emerald green meadows and Mt Aso’s lava landscape in the backdrop. On the way up, everyone will pass by the crater vestige Kusasenri, which is one of the most luscious green grass fields you can imagine. Most people stop here to have picnics at the lake or rent horses for a guided tour across the hills.
From Kusasenri it’s only a couple of kilometres to the place everyone has come to see – Mt Aso’s northernmost crater or crater number one. You can stand right on the perimeter, looking into the deep turquoise colour of the crater lake, whose lava temperature hovers between 1000 to 1200 degrees Celsius. At a 600m width and 130m depth, many signboards warn adventurers not to climb across the boundaries. Some do though to collect the canary yellow igneous rocks, but these and other colourful rocks can be bought from the vendors along the main trail around the crater, which is a lot safer.
There are several concrete emergency shelters dotted across the area should the volcano erupt. Japanese officials have assured visitors that these shelters are mainly used for picnics or as a cover from the rain, because the whole crater area is evacuated immediately if the volcano becomes too active. Warning systems are installed on the entire mountain range and all staff members are well trained at evacuation and other emergency procedures should the volcano erupt.
That’s unlikely to happen, but the observation decks are sometimes closed, depending on the wind direction. Inhaling the toxic volcanic gases is a health hazard and the crater’s fumes are closely monitored at all times.
If the crater is closed for a few hours, try and explore the peaks. Several trails will lead you through a rugged moon-like landscape with lava rocks, leading to the top of Mt Taka, which at 1592m is the highest of the five peaks that make up Aso’s central cone group. The further up you hike, the greener and denser the vegetation becomes and you will come across waterfalls and wildlife.
If you’re only there to look at the active crater, a couple of hours will give you enough time to walk the main trails and take pictures of Aso’s highlights. But you can easily spend a whole week hiking the five peaks and doing some sightseeing in the surrounding rural areas without getting bored.