Guide
Bungo Kaido (Nijuko Pass) is a historic mountain pass located in Kuragari, Aso City, Kumamoto Prefecture. This area was once a vital transportation hub for the Bungo Kaido, the main route connecting the Higo and Bungo provinces. The most striking feature is the approximately 1.6km stretch of stone paving, roughly 3 meters wide, which remains remarkably well-preserved. These cobblestones were originally laid to prevent the road from eroding due to heavy rain and wind on the steep slopes, preserving the atmosphere of the Edo period. The site offers a harmonious blend of historical ruins and the vast, sweeping natural landscapes of the Aso region.
The route is a historically significant path said to have been developed by the famous daimyo Kato Kiyomasa. During the Edo period, it served as a major route for the Hosokawa clan's Sankin-kotai (alternate attendance) processions. The stone paving was a sophisticated engineering solution of the time, designed to stabilize the terrain against the elements. Walking this path allows you to physically connect with the history of the countless travelers and goods that once traversed this pass. The area also holds significant cultural value, with historical records noting that the famous Edo-period figure Katsu Kaishu once wrote about the beautiful scenery of this region.
The centerpiece of your visit is the 1.6km cobblestone path. As one of the longer stretches of preserved stone paving in Japan, it offers a rare opportunity to observe the engineering techniques and craftsmanship of the era. As you walk, you will be surrounded by the undulating topography of the Aso caldera. The scenery is particularly magical during twilight, when the sky transitions through a beautiful gradient of orange to deep blue, casting a serene and nostalgic light over the ancient mountain pass.
As an outdoor historical site, the pass is accessible year-round, and each season offers a different facet of nature. During the bright daylight hours, you can clearly observe the textures of the stones and the surrounding lush vegetation. For those seeking a more atmospheric experience, visiting at dusk allows you to witness the dramatic color changes in the sky, which adds a sense of timelessness to the historical landscape. For hiking purposes, visiting during daylight hours is highly recommended for safety and visibility.
Visitors can enjoy a peaceful hike along this historic trail. A round trip to the bottom of the pass takes approximately 2 hours. Walking on the actual stone paths allows you to experience the physical sensation of what ancient travelers felt centuries ago. Because the route is well-maintained, it is suitable for a casual hike rather than a strenuous mountain climb, making it an accessible way to experience history through movement.
The area around Nijuko Pass is dotted with spots to enjoy the natural beauty of Aso. For instance, the 'Kabuto-iwa Observatory' along the Milktrail and 'Nishitoura Park' offer stunning views of the Aso Outer Rim. Additionally, natural spots like 'Ochaya Sensui,' where fresh spring water flows, allow you to fully immerse yourself in the natural landscape of Aso alongside your historical exploration.