The peak actually goes by two names, and the locals don’t seem to know which one is correct. Most people call it Misumi-dake (三角岳) but others use the name Sankaku-dake (三角岳).
The mountain is a good day hike from Kumamoto city and offers spectacular panoramic views.
There aren’t any convenience stores in Misumi, so make sure you pick up supplies/snacks in Kumamoto before boarding your train.
Make sure you check the bus schedule in advance. Meitetsu’s bus website is a bit convoluted but you can search for the bus by plugging in starting from 高蔵寺駅北口 and going to 植物園. It’s only 7km to the trailhead so if you have a couple of people then a taxi shouldn’t be too costly.
I recommend not only downloading the digital map from YAMAP, but also printing this simple paper map that you can use to cross reference against the numbered signposts on the approach to Miroku.
The trail described in this video isn’t well used between signposts 2 and 7. One safer alternative would be to take what I call the “adventure course” up to the Buddhist pagoda rock carvings and then retrace your steps back to signpost 2 and then continue up the well-maintained main trail to the right pointing to signpost 9.
It should take 2 – 3 hours to do the hike (longer if you take it slow and have lots of breaks). After you reach the forest road at the bottom of the loop, continue straight past the elementary school and then meander back toward the station. Instead of crossing the same bridge on the approach, you might want to head down to the 7-11 and cross over the smaller bridge further east. Just use Google Maps on your phone to navigate your way back to the train station. There’s only about 1 train an hour, so take a photo of the train schedule at the station before you start your hike.
Make sure your streetcar goes to Higashi Yama. Get off at the last stop. Board the streetcar on the back at exit at the front (pay the fare in the fare box next to the driver).
The rock formation is actually called Ochinai-ishi (not Ochinai-iwa). It’s basically the rock that won’t fall down and it’s a huge one. There’s a shrine built into a rock alcove on the rock.
I’d like to go back and climb some of the other trails on the mountain, so if you live in Okayama and have explored the trails of Misao, feel free to leave a comment and let me know how they are.
This hike might be better done in reverse, following my descent path to reach the forest road before continuing on to Aoidake and the optional ascent of Keragatsuka. That way, on the descent, you can just follow the road all the way down to the hot spring. If you want to do this, then turn right out of the station and walk along the road, cross over the train tracks and veer left and then right, following the sign that says 青井岳登山. Follow the tape marks all the way up to the forest road and then turn left and traverse through the clearcut area to the trailhead.
Aoidake Onsen is an excellent place for a post-hike bath. It’s open from 9am to 9pm (Last entry 8pm) and costs 480 yen on weekdays and 580 yen on weekends and holidays. There’s a great toilet in the parking lot of the hot spring (as there’s no toilet or much of anything at Aoidake train station).
A taxi should cost less than 2000 yen from Satsuma-Imaizumi station (it cost me around 1800 yen). I ended up traversing over the far side of the mountain and walked down toward the lake, where I hitched a ride to Nigatsuden station. It’s much easier to hitch a ride if you made a sign saying Eki (train station). The path on the far side of the summit is well-marked with pink tape and it’ll drop to a forest road. If you turn left you can apparently loop back to where you started the hike, but if you want to go toward the lake then turn right and follow the road and turn left at the next junction and you’ll soon reach route 247. If you want to hitch from Satsuma-Imaizumi station then walk out of the station, turn right, and then another right on route 28 which will take you to Ikeda. The shoulder is narrow here, so make sure you walk up the road for 5 minutes to 田之上商店, a small shop on your right, where there is a wider shoulder here so cars can potentially stop.
You could also combine an ascent of Mt. Kiyomi together with Mt. Kaimon.
If coming by car, then there is a parking space just below the tea fields across from the first torii gate.
The hike to the summit is pretty straightforward. The trailhead to Kasayama is hard to find as it’s completely unmarked. From the trailhead of Mt Tsuno head down the road to the right of the small shrine and walk straight toward the peak which sits due east. The trailhead is on the same street as Sakaide St. Martin’s Hospital and it very close to a cemetery named 坂出さくら離宮. Here is a pin on Google maps. Cross over the chain spanning the concrete driveway and walk along the edge of the cemetery and follow the trail up to the summit. The path steepens just before the summit, climbing through a short rocky section. The panoramic views from the summit of Kasayama are nothing short of spectacular, but be warned: there is absolutely no shade on the narrow summit, so take care on hot sunny days.
I forgot to mention in the video, but there is a swing and pull-up bar on the summit of the mountain, which is where I did the pull-up in the closing credits.
There are two main routes up the mountain, either via the cable car (or the trail running alongside) or from Yabitsu-tōge.
Yabitsu-tōge route:
If coming by car, there’s a small parking lot at the trailhead. Otherwise, you can access it by infrequent bus from Hadano station (秦野駅) on the Odakyu Odawara line. The trail itself is very well-used and easy to follow, making it nearly impossible to get lost. On a clear day, there are nice views of Mt Fuji, Tanzawa, and Yokohama city. The summit itself is a bit run down, with antenna, decrepit shrine buildings, and picnic tables. It’s not a mountain to climb if you’re looking for beauty, but it is quite convenient for those of you based in Tokyo.
Local trains on the JR Kinokuni line are infrequent, so if coming from Osaka by train, please check the connection times before departing.
Descent route description:
For some reason, there aren’t any signposts on the mountain, making it quite easy to take a wrong turn if you’re not careful. The route from the temple to the summit is pretty straightforward (if you follow the instructions in the above video). From the summit, head north along the broad summit plateau and ignore every trail heading off the ridge until you reach a big picnic table with bamboo seating. This is a 3-way junction. Take the trail on the far side of this table as it heads in the direction of the buildings at the foot of the mountain. Don’t take the trail to the left marked for 紀三井寺 as it heads back to the temple. Drop down the steep trail and turn right at the first junction (there’s a small signpost pointing back in the direction you just came marked for 一本松広場). Continue straight and ignore a trail on your left heading down into the forest. Instead, veer left and straight here for a short distance until reaching another unmarked junction at a rock wall and stone gully. Turn right here and enter the gully, following it down to reach a shrine, cemetery, and temple. Once you reach the houses, zigzag your way back to the station (using Google Maps to help guide you).
The full route from Iwama (岩間駅) to Fukuhara (福原駅) is well-marked, with white signposts for Kasama Wagakuni-Atago Hiking Trail at regular intervals. Be warned that it is a long route (15.8km) with a lot of up-down, so make sure you bring plenty of liquids and give yourself at least 4 hours (though it’ll probably take closer to 6).
Traverse route:
From Iwama station, follow the signs to Mt Atago. The video above describes the route to Mt Minami in great details. From Mt Minami stay on the main trail, following the signs toward Mt Nandai (難台山). After hiking up and down over a few undulating hills, the path drops steeply via fixed ropes to Dango-ishi Pass (団子石峠). Turn left on the paved forest road and then an immediate right (past a couple of parking spaces). It’s a long hike up to Mt. Nandai over a series of smaller peaks. Take your time and follow the signs as it leads past a number of boulders, especially Dango Boulder, Shishiga-han Boulder and Byobu Boulder. Just before the summit the terrain gets quite rocky and the broad summit is a great place for a break. You’re halfway there distance wise, so on the far side of the summit drop down the steep trail and up and over a few more hills until you drop down to another paved road at Dōrokushintōge (道祖神峠). Follow the signs and pass through a forest briefly before reaching a red-roofed structure and some green signposts for Wagakuni (ハイキングコース吾国山頂). Climb up and cross over the forest road where it is a very steep and hard climb to the summit. The top is marked by a rustic shrine and it overlooks the mountains of Oku-Nikko. You can see Mt. Nasu, Mt. Nantai, Mt. Okushirane, Mt. Hiuchi, and Mt. Sukai on a clear day. From here take the trail to the right of the shrine (if you are facing the building) and drop through a forest of towering beech trees. There are roped off walkways here that meander past all of the big trees, but you’ll basically want to head down past a small pond and into the forest. After 30 minutes you’ll reach the edge of a village and will pop out into civilization. Continue following the signposts as they take you to Fukuhara station.
Access:
Iwama station takes about 2 hours from Ueno on the JR Jōban line. Fukuhara station is also about 2 hours from Tokyo. You may find it faster to change to the Kanto Railway train at Shimodate station (下館駅) instead of staying on the JR Mito line all the way. If you change at Shimodate, take the train to Moriya (守谷) station, where you can change to the Tsukuba Express for Akihabara. Otherwise you’ll need to change back to the JR Jōban line at Tomobe station.