Please be aware that due to a helicopter crash in January 2026, access to the Nakadake Crater is currently restricted. This is expected to last for several months. I will update this article as and when we can expect it to reopen. The tourist centre, museum, and hiking routes are all currently open.
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Not every trip goes to plan.
Now I’m fairly loose when I plan my Japan trips. I will normally set two or three things that I am committed to doing/seeing, then wing the rest once I land. I find this enables me to really soak in the country, instead of rushing around trying to squeeze every last sight in. It doesn’t work for everyone, but it does for me.
For this particular trip, visiting Aso Caldera was not on my to do list.
In fact, Kyushu wasn’t on my agenda at all. For this trip, I had built an entire Japan itinerary around a single goal: climbing Kitadake, Japan’s second-highest mountain. I’d been training for about two months, putting in gym time specifically to prepare for it. Stair master, incline walks. All the really boring stuff that I probably didn’t need to worry too much about (I’m reasonably fit) but that helped me manage my excitement for my trip.
Then, five weeks before departure, I tore my adductor.
The decision to cancel the Kitadake hike hurt almost as much as my groin, and I put it off for as long as I could. It’s a climb I’d wanted to do for years, and I was hopeful my adductor would heal in time. However, with mountain hut spaces limited and not wanting someone else to miss out, I pulled the plug with just over two weeks to go. I was miserable. I even considered cancelling my Japan trip altogether. But with no chance of a refund from my airline and rescheduling costing more than I was willing to pay, I instead decided to explore Kyushu for the first time. I decided to base myself in Kumamoto, mainly due to its proximity to Aso. It looked promising, offering some gentler hikes, and seeing an active volcano is always going to be an experience in my book. Despite all of that, when I boarded the train to head out, I was still very much resenting the fact I wasn’t climbing Kitadake.
Aso fixed that within about twenty minutes of arriving.
Getting There
Access from Kumamoto to Aso is via train from Kumamoto Station along the Hohi Line. There are a number of direct trains, including the themed ‘Aso Boy!’ car with an adorable dog mascot, but these will need advance reservations. I only found out about those after my trip so I went via local trains which required a transfer at Higo-Ozu Station. Both direct and local trains are covered in the All Kyushu Area rail pass. Check this guide to see if a rail pass works for you.
The train journey itself was memorable. Many local trains in Japan have a window at the end of the carriage which lets you look out over the driver’s shoulder and onto the track ahead. This may be a thing in other countries, I’m not sure. It’s not a thing in the UK. Either way, I enjoyed taking in the scenery as we headed into the countryside. As we began to climb, the train had to perform a number of switchbacks, zigzagging its way up the steep slope, which was a new experience for me.
After about 90 minutes we arrived at Aso Station. From there I took the bus to Asosanjo terminal. The buses themselves depart frequently, although their exact times depend on the time of year. I recommend using the JapanTravel app for precise timings, although usually the first bus is around 9:30am and last at 2:30pm. The journey takes about 40 mins and costs ¥1,000 one way. On arrival at Asosanjo, there is a shuttle bus that takes you to the crater. This replaces the ropeway which has been closed for a few years due to earthquake damage, although worth noting many blogs don’t mention this, including the official Visit Japan website…
The shuttle bus to the crater takes about 5 mins. Or, you can walk the last leg which is about 30-40 mins. (Which I did.)
If that all sounds a bit too much for you, there are dedicated tours available from Kumamoto to Nakadake crater. Check them out here.
However you choose to get to Aso, one thing is the same. The scenery is spectacular. When you think of volcanoes, you tend to think of coned mountains with a crater on top. Aso is not that. This is an entire landscape, towns, roads, farmland, which all sit inside a caldera that is roughly 25 kilometres across. It contains a central group of five volcanoes, referred to as the Aso Gogaku, as well as many smaller volcanoes. The caldera itself is believed to have been formed by four major eruptions over 100,000 years ago.
A Point On Visiting Aso Caldera
After climbing up to Nakadake crater, I made a decision that in hindsight I got wrong, so I will share that with you now to help you avoid making the same mistake.
I chose to do my hike rather than going to the viewing crater first. I thought by going later it would be less crowded. However the viewing platform can close sporadically if the activity in the volcano increases to a point that is deemed a health risk. This happened while I was hiking nearby, and in fact I could hear the announcements over the tannoy a kilometre or so away. It didn’t reopen again that day.
I’ll add it to Kumamoto Castle on my ‘list of reasons to return to Kyushu.’
If the viewing platform is open, do that first. You’re welcome.
The Hike
Turning off the road and onto the hiking trail, the scenery before me was unlike anything I have seen before. I imagine it is what walking on the moon would feel like. (If you happen to have ever been to the moon, please go to Aso and then let me know your thoughts.) In my memory, the ground was jet black and gravelly. Looking back at the photos, it appears to be more of a greyish black dust, presumably ash from Nakadake. Either way, I remember the smile that broke across my face, and for the first time on this Japan trip, I was simply buzzing to be there. It’s worth mentioning this was my second time walking on volcanic ground, my first being four years previously as I reached the summit of Mount Nantai. The difference was that Nantai’s ground consisted of a coarse red and purple gravel due to the iron content. The ground around Nakadake was not that at all. (It reminds me of the sunabashiri descent from Mount Fuji, a volcanic slope you can run down, but the time between the two hikes may be clouding my judgement.)
What I can say with certainty, was that for the first time in almost seven weeks, my groin did not hurt.
I realised it about an hour into the hike. I came across a steep boulder scramble. I looked at it, and immediately thought my groin wouldn’t handle it. It then occurred to me I couldn’t remember it causing any pain since the morning. Whether it was the adrenaline, the terrain, or simply the fact that I’d stopped thinking about it, I honestly don’t know. But as I tentatively scrambled up those boulders, my smile just kept on growing.
The Evacuation
Two hours in, and not far from the summit of my hike, a voice began to echo out across the caldera. It was a little surreal, I was easily a kilometre or two away from the nearest building, and all alone in what had until that point been relative silence. The announcements were in Japanese, Chinese then English. It was hard to make out exactly what was being said, but after a few minutes and a few loops of the announcement, I understood.
They were evacuating the crater.
My mind was at a loss. I was suddenly reminded that I was standing on active geology. Images of an apocalyptic explosion, lava and stone raining down around me played out in my mind. (I can be a bit overdramatic it would seem.) I was getting ready to descend, until a Japanese couple, apparently veterans of Aso hiking, informed me that it was just for the viewing platform below, due to an increase in gas concentration. I thanked them, relaxed, shot some videos, then continued my hike.
As mentioned earlier… the platform did not reopen.
The Black Sesame Ice Cream
I am including this because it was that damn good.
At Asosanjo Station there is a visitors centre. I have an open mind when it comes to trying new food, and whilst perhaps not the most daring of tastes I have tried, the pure black ice cream certainly looks interesting.
It was sensational.
It was a perfect way to round off what had been a trip that had genuinely surprised me. I had expected to enjoy it. (Hiking around an active volcano. How could I not have.) What I hadn’t been prepared for was the scale, the scenery, and the sheer thrill of it all. I decided to take a bus back from Aso Station to Kumamoto, and as I relaxed after the most active day I’d had so far, I promised myself I’d return. To do the viewing platform. To do more of the trails. To have more of that ice cream.
Practical Information
- Volcanic activity: Check the alert level here before you visit. Crater access closes frequently.
- What to bring: Sturdy footwear. Layers in the colder months, hat and sun cream in the warmer months. Cash for the visitor centre.
- Not into hiking? No problem. In fact, there are a host of activities you can participate in, from helicopter tours to horseback riding.
- Time needed: Full day from Kumamoto.
The Honest Summary
I arrived at Aso flat, injured, and mourning a cancelled hike. I left having scrambled up a volcano, heard an evacuation announcement echo across an ancient caldera, and eaten the best ice cream in Japan.
The Kitadake dream is still very much alive. It’ll happen. Japan has the Hyakumeizan, the 100 famous mountains of Japan, and I hope to complete as many of them as possible. My trip to Aso enabled me to tick another off the list, which I am grateful for, but not nearly as grateful as I am for the experience. I have 85 or so mountains still to go to complete the Hyakumeizan, and if they’re at least half as special as Aso was, I’ll be a very happy man.
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