Aso Kuju National Park features Japan’s largest active volcanic caldera and the dramatic Kuju mountain range, offering diverse outdoor recreation opportunities including hiking, hot springs, and panoramic volcanic landscapes.
Aso Kuju National Park, located in Kyushu’s Kumamoto and Oita Prefectures, is renowned for its volcanic topography centered on Mount Aso, which boasts one of the world's largest calderas spanning approximately 25 kilometers in diameter. The park's landscape is dominated by this volcanic caldera containing active volcanic vents and vast grasslands that contrast sharply with the rugged Kuju mountain range situated to the east. Mount Kuju, the highest peak in Kyushu at 1,791 meters, provides alpine habitats rich in unique flora and fauna. Established in 1934, this protected area preserves dramatic volcanic scenery formed through millennia of activity, with Mount Aso's crater frequently emitting steam and occasionally erupting, offering visitors an insight into dynamic geological processes. The park supports varied ecosystems from grasslands sustaining wild horses to forested highlands home to rare alpine plants. Outdoor enthusiasts can engage in hiking ambitious routes, including the Kuju mountains' ridgelines, horseback riding on the prairie, hot spring bathing (onsen), and scenic drives around the caldera perimeter. Notable landmarks include the Nakadake crater with its visible lava lake, Mt. Taka and Mt. Naka, and the surrounding plateau filled with vibrant seasonal flowers. Visitors often combine exploration with cultural experiences in nearby towns rich in history and traditional agriculture. The park’s accessibility and range of landscapes make it a popular destination for nature lovers and those interested in volcanology, mountain trekking, and relaxation in hot springs.
Mount Aso’s central active volcanic crater with visible steam vents
Kuju Mountain Range – highest peaks in Kyushu with alpine ecosystems
Grassland plains home to native wild horses
Hot springs and traditional onsen resorts scattered around the caldera
One of the world’s largest calderas formed from repeated volcanic eruptions, featuring a central active crater with visible fumaroles.
A series of rugged peaks including Mount Kuju, providing alpine hiking routes and diverse plant communities.
A popular vantage point overlooking the vast caldera with panoramic views of Mount Aso and surrounding grasslands.