Mt. Aso's Eboshidake and Kishimadake hike

The Aso caldera and its 5 peaks

Mount Aso isn't a single mountain but a group of volcanoes inside a vast caldera — one of the largest in the world, covering about 350 km² with a circumference of roughly 100 km. It's part of Aso-Kuju National Park, which spans central Kyushu and also takes in the Kuju mountains. Five peaks rise from the caldera floor: Nakadake 中岳 (1,506 m), Eboshidake 烏帽子岳 (1,337 m), Kishimadake 杵島岳 (1,321 m), Nekodake 根子岳 (1,433 m), and Takadake 高岳 (1,592 m), the highest of the group. Whichever peak you climb, you get the same wide view: the town of Aso in the distance, sitting in the northern part of the caldera, with roads and railway lines looping around the base of the peaks.

The central crater group can be reached by car or bus, and the hiking trails start at an altitude of around 1,100 m. Routes circle the four main peaks, but Nakadake (the active volcano) and Takadake behind it are often closed off due to volcanic gas and elevated activity — access depends on the daily alert level, so it's worth checking before you go. Nekodake, the fifth peak, has its own separate trailhead further away.

We parked at the main parking lot near Kusasenri (500 yen per day), which is the best starting point for the hikes here. There are shops, toilets, and the adjacent Volcano Museum, though it was closed during our visit because of the pandemic.

Before starting the hike, stop first at the other parking lot — the one by the Nakadake crater. There's an information center there with an English-language hiking map (see image below) showing the approximate times and distances for each trail, worth picking up before you set off.

Eboshidake and Kishimadake hike

The green routes marked on the map are the two peak loop hikes around Eboshidake and Kishimadake. Together, the two hikes took us 2 hours and were not particularly demanding. The Kusasenri-ga-hama 草千里ケ浜 and Eboshidake loop was the easiest of the two, crossing from one side of the mountain to the other with open views over the Kusasenri grassland and the surrounding caldera.

Kishimadake was a bit more demanding, with some steeper sections, but nothing technical. The paths are clear and well marked throughout. Hiking shoes are worth having, since the trail crosses loose volcanic rock that can be slippery in places.

Nakadake crater

Nakadake has been active since prehistoric times and remains one of Japan's most active volcanoes, with eruptions recorded as recently as 2021. During our visit the crater itself was closed to visitors. Even from a distance, the volcano made an impression: a steady, forceful blast of gas from the crater, accompanied by a deep, continuous rumble that made it feel like it could erupt again at any moment.