Yatsugatake (八ヶ岳) ice-climbing - Sanjahou couloir (三叉峰ルンゼ)

Route name: Sanjahou runze (三叉峰ルンゼ)

Mountain: Yokodake (横岳) in the Yatsugatake (八ヶ岳) massif

Map sheet: 33 [Yama-to-kougen-chizu (山と高原地図) series]

Length: approx. 400m

Time: 6 hours to summit ridge

Grade: WI3-4 / overall grade 3 winter alpine route

Getting there:

If traveling by train, take a Super Azusa limited express train from Shinjuku (新宿) to Chino (茅野 approx. 3 hours). Outside the JR station at Chino take a bus to Minotoguchi (美濃戸口 approx. 1 hour). This is the gateway to the Akadake-kōsen side of Yatsugatake.

From the car park start hiking up the trail that is signposted to Akadake. The walk-in takes around 3 hours by map time. It is split into 3 stages. The first hour brings you past a series of buildings and on a little further to the Minoto-sansō (美濃戸山荘) hut. The next hour follows the rindou (forest road) until it finishes at a bridge across the sawa (stream). From the other side the path narrows and meanders alongside the sawa for another hour or so until you reach the hut at Akadake-kōsen. This hut serves as basecamp for all the routes in the area.

Description:

From the hut you need to follow the hiking trail in the direction of the pass at the start of the Nakayama ridge (中山尾根). After about 15 minutes you will reach a small bridge. Leave the trail and turn left right after this bridge.

Keep heading up for around an hour, taking the right fork at a couple of junctions. With the Sekison ridge (石尊稜) on your right, you will eventually arrive at the start of the Sanjahou couloir.

In early December the first icefall is at its tallest, around 12m of vertical before it eases off a bit. It could also be rather thin. By January it is usually a bit shorter due to snow accumulation at the bottom.

After the icefall, continue up the gully on steep snow with occasional old pitons and bushes in the left wall for protection or anchor building to finish the pitch.

The route now continues up frozen waterfalls of varying lengths up to 10m in height separated by stretches of steep snow inside the gully. Protection throughout these first few hundred metres is ice screws in the waterfalls. It can be simul-climbed if you're confident, but 3-4 pitches should suffice to reach the end of this section.

Eventually a large open ledge is reached, which marks the end of the narrowest section of the gully. From here there are two possible directions, heading up a frozen waterfall left or right. Take the right fork and climb the icefall and then a 6-7m rock chimney above, and belay at the top on two Petzl bolts on the left wall.

From here the angle eases off a little and the route continues up onto the upper face alongside the Sekison ridge on climber’s right. The face opens up gradually, and the rock gendarmes of the Daidoushin (大同心) and Shodoushin (小同心) can be seen off to the left.

When you reach the headwall, you need to move up to the right and around a corner to a peg belay on the upper section of the Sekison arête. From here you have two options to finish. The easiest option would be to traverse a full length to the right, and then climb easy slopes to gain the summit ridge hiking trail.

The more interesting option is to climb the final two pitches of the Sekison arête. The first pitch takes the initial groove at grade III, then continues up steeply and sharply on the arête, before heading round to the right and up to belay on a rock spike. Protection is rather sparse, but the pitch is well featured.

Next, continue up and into a broad gully on steep snow, which leads to the top after around 70m.

Once on the main hiking trail, head left up the ridge to the summit of Yokodake (横岳), or right towards Akadake (赤岳). After about an hour of moving along the ridgeline towards Akadake things level off a little, eventually reaching a junction marked by a stone Buddhist statue of Jizo. The statue marks the entry point to the Jizo ridge on the right, and this is the quickest descent back to the Akadake-kōsen hut. This path is steep but straightforward. An hour of descent will bring you down to the Gyouja-goya hut.

Overall:

A superb gully route up the face to the left of Sekison arête, with a stunning and airy finish to gain the summit ridge. One of the classic winter gully routes in the area, although ice conditions can be fickle some years. Take about 6 ice screws, a couple of smaller cams, and a selection of slings and quickdraws for protection.