Central Kyūshū is dominated by sparsely populated, grassy highlands, in places rising to substantial peaks, which offer some of the island’s most magnificent scenery and best walking country. These mountains are relics of ancient volcanic upheavals and explosions of such incredible force that they collapsed one gigantic volcano to create the Aso caldera, the world’s largest crater. Today the floor of the caldera is a patchwork of fields like many tatami mats, and the surrounding uplands form a popular summer playground, but the peaks of Aso-san at its centre provide a potent reminder that the volcano is still very much alive. Most people come here to peer inside its steaming crater, eruptions permitting, and then scale some of the neighbouring peaks or walk over the lush green meadows at its base.
All this subterranean activity naturally means a wealth of hot springs to wallow in, mostly within the caldera itself, although there are a few gems hidden deep in the highlands. One is the picturesque village of Kurokawa Onsen, squeezed in a narrow gorge on the Senomoto plateau, which makes a great overnight stop on the road to Beppu. The village lies a few kilometres off the Yamanami Highway, the main route between Aso and Beppu, providing a spectacular mountain ride through the Aso-Kujū National Park. Heading in the opposite direction, another dramatic road climbs over the crater wall and heads southeast to Takachiho. Perched above an attractive gorge of angular basalt columns, this is where the mythical Sun Goddess Amaterasu hid, according to legends about the birth of the Japanese nation. A riverside cave and its neighbouring shrine make an easy excursion, but a more compelling reason to stop here is to catch a night-time performance of the story told through traditional folk dances.Read More
The train from Kumamoto changes direction twice as it zigzags up the formidable wall of the Aso Caldera. This ancient crater, measuring 18km from east to west, 24km north to south and over 120km in circumference, was formed about 100,000 years ago when a vast volcano collapsed. As the rock cooled, a lake formed, but the eruptions continued, pushing up five smaller cones, today known collectively as Aso-san (阿蘇山). At the eastern end of the chain lies the distinctively craggy Neko-dake (1433m), while the next peak west is Taka-dake (1592m), the highest of the five summits, and its volcanic offshoot Naka-dake (1506m). West of here lie Eboshi-dake (1337m) and Kijima-dake (1321m). Of the five, only Naka-dake is still active; it’s really just a gash on the side of Taka-dake, formed by a volcanic explosion which created a secondary peak. Naka-dake’s most recent eruptions occurred in the early 1990s, since when it has calmed down considerably, but it’s wise to treat the mountain with respect. Notices are posted in the train and bus stations when Naka-dake is closed, but if you plan to do any long-distance walks around the crater it’s wise to check at the information office. Anyone suffering from asthma or other respiratory problems is advised not to approach the crater rim because of strong sulphur emissions.
Seven daily buses shuttle visitors from the terminal outside Aso Station on a dramatic forty-minute journey up towards the peaks of Aso-san. As the road climbs up to the pass between Kijima-dake and Eboshi-dake, you look down on the perfect cone of Komezuka, the “hill of rice” – its dimpled top is said to have been created when Takeiwatatsu-no-mikoto scooped up a handful of rice to feed his starving people. Turning the other way, you get your first glimpse of Naka-dake’s gaping mouth across the grassy bowl of Kusasenri plateau, speckled with shallow crater lakes.
On the plateau, the bus stops outside the missable Aso Volcano Museum (阿蘇火山博物館), though you might want to get off here to climb Kijima-dake (杵島岳; 1321m), which rises behind the museum. The paved path from the far northeast corner of the car park takes you on an easy thirty-minute climb, rewarded with more views over the caldera, and then down into Kijima-dake’s extinct crater. From here, you can descend via a ski slope to join a path alongside the road to Naka-dake; the whole walk should take under ninety minutes.
Rather than backtracking, you could take a great hiking trail round the crater’s southern rim to the summit of Naka-dake, followed by a possible side trip to Taka-dake (高岳) and then down to the northeastern Sansuikyō Ropeway. It’s not too difficult as long as you’ve got good boots, plenty of water and you keep well away from the edge. To pick up the path, follow the boardwalks heading south round the crater across the Sunasenri plateau.
One of the most popular hot-spring resorts in Japan, KUROKAWA ONSEN (黒川温泉) is made up of twenty-odd ryokan, which lie higgledy-piggledy at the bottom of a steep-sided, tree-filled valley scoured into the Senomoto Kōgen plateau (瀬の本高原), some 6km west of the Yamanami Highway. The village is completely devoted to hot-spring bathing and most of its buildings are at least traditional in design, if not genuinely old, while yukata-clad figures wandering the lanes add to its slightly quaint atmosphere. The village is particularly famous for its rotemburo: there are 24 different locations in total, offering rocky pools of all shapes and sizes. Out of the main tourist season, when the crowds have gone, it’s well worth making the effort to get here, and Kurokawa makes an excellent overnight stop, if you don’t mind paying a little extra for accommodation.