Mount Kosho is central to the myths and the legends of Akizuki. The town’s importance as a strategic stronghold is drawn from the ring of protective mountains, which rise towards Kosho’s peak. The hike to the top takes 4-6 hours and the route is clearly signposted the entire way. The route is full of shrines, ruins and hiding places from the days of the Akizuki clan. While the route is not too challenging it can be steep in sections so sturdy shoes with good grip are advised.
There are two options on where to start. Starting from the upper car park saves about 1-2 hours (3.6 km). The trail from the lower car park leads to the upper, and then onwards to the top of the mountain.
Lower car park to upper car park (1.8km - one hour)
- Take the narrow road that goes up past Honkaku Temple to reach the lower car park. From the lower car park, head uphill, with the river to your right.
- At the edge of the forest, the trail passes alongside a house, and then through a torii gate. The path at this point is well-surfaced with concrete, but becomes slippery when wet.
- Keep the stream on your left until the concrete surface ends and then cross the wooden bridge to start on the dirt path. The gradient increases slightly at this point, and the path alternates between being well maintained and washed-out.
- Continue along the path. You’ll have to cross the stream a couple of times, sometimes by bridge, and sometimes using stepping stones.
- Towards the upper car park, the path steepens again, with a couple of hairpins. There’s a low-set, moss covered picnic bench, and then one final, poorly-maintained bridge over the stream that takes you up to the upper car park.
Upper car park to summit (1.1km - one to two hours)
- Inspect the map on the signboard before you begin the climb. The path from here becomes less well-maintained, and at times, shares its course with the stream.
- From the signboard, follow the path up the left hand side of the stream until it seems to disappear at the foot of a steep earthen embankment covered in trees.
- There are red markers on several of the trees to the right side of the embankment. Follow these and you’ll rejoin the path.
- Keep up the mountain on the left side of the stream, until the path is blocked by a black and yellow rope that forces you around to the right, across the stream.
- The path briefly levels off until it meets the next valley, and then begins to steepen again. Keep ascending until, at the top of the valley, you find a small water-fed pool from which you can drink.
- From here, the path heads off to the left, and becomes narrower and rockier. The plantation cedars of the lower mountain are replaced by original primeval forest. Moss covers nearly every surface. Look out for hidden statues, faces worn by time and weather.
- Shortly after leaving the pool you’ll come across a signpost which points to Mt. Kosho (古処山) in either direction (left 15 mins, right 25 mins). Choose one and follow it to the summit.
- Near the top of the mountain, numerous smaller tracks lead off the main path. If you’re feeling adventurous, explore these, as they usually lead to gems hidden in the forest. To the north side of the summit there are the moss covered ruins of the Akizuki Kosho Fortress, in such bad repair it is hard to distinguish them from the natural rock.
- Follow the main path upwards until you reach the summit where there are a few benches to rest on and enjoy the great views across Fukuoka Prefecture, as well as a small shrine.
Summit to the General’s Hiding Place and Inner Sanctuary (optional one hour round trip) Beyond the summit of Mt. Kosho are two extraordinary natural features that can be reached via a rocky climb (it really is a climb): the General’s Hiding Place and the Inner Sanctuary.
- From the summit of Mt. Kosho, head up the wooden and follow the signs to the General’s Hiding Place (大将隠し).
- The path first follows the ridge and is often overgrown. It is steep at points, but manageable, and eventually flattens out. The signs to the General’s Hiding Place (大将隠し) point left, and the path takes you through a rocky crevice at which point it becomes increasingly steep.
- After about ten minutes of climbing downwards, you’ll reach the General’s Hiding Place, a two-meter wide cleft in the rock that can be explored with a flashlight.
- To reach the Inner Sanctuary head right and down from the General’s Hiding Place. Use the chains to climb down the rocks (near vertical), and carry on for about five minutes until you find the Inner Sanctuary (奥の院), a 30cm wide crack in the rock that opens up into a series of small caves. Explore and then head back up to the summit the way you came.
The return takes about two hours and simply follows the path you came up on.