Mount Tenzan Nanamagari Pass Course

The Mount Tenzan Nanamagari Pass Course is the longer of the two main approaches to the 1,046 m summit of Mount Tenzan within Tenzan Prefectural Natural Park, starting from the Nanamagari trailhead parking area, reachable only by car roughly 1 hour from JR Saga Station. The round-trip route covers 10.5 km and gains about 638 m, typically taking 4 to 4.5 hours, making it the most demanding hiking route in the Saga hiking cluster. The lower trail winds through cedar forest on a dirt path with numerous switchbacks (nanamagari means 'seven turns'), transitioning above the tree line to open grassland with loose, sometimes rocky footing on the final ridge approach to the summit. There is no technical scrambling required, but the sustained distance, elevation gain, and exposed upper section call for hiking boots, layered clothing for changing ridge weather, and a full day's supply of water and food. Trail junctions in the forested lower section are not consistently signposted, so a map or GPS track is recommended to avoid wrong turns. Key landmarks include the switchback section that gives the course its name, a mid-route junction with the Jogu Course near the ridge, and the summit itself, which offers panoramic views over the Sefuri range and, on clear days, toward the Ariake Sea. There are no water sources, huts, or refuge shelters anywhere along the route, so hikers must carry everything needed for the full round trip. The course is most rewarding in May and June, when the forest is freshly green, and in October and November, when the summit grassland turns gold; winter brings frost and occasional ice to the exposed upper ridge, and summer heat and humidity make the long climb strenuous.