Location: Oshamambe, Yamakoshi-gun/Imakane, Setana-gun
Elevation: 972m (~800m elevation gain)
Length: Half-day+ (~12km)
Hiked on: January 17th, 2017
The hike begins at the end of road going to Futamata Radium Hot Spring, just off National Road 5 between Kuromatsunai and Oshamambe. As the road climbs up the valley there a turn off to the left which goes to the onsen; instead of turning keep going straight and you’ll get to the point where the snow-clearing ends. Park your car there and it’s a 3km walk along the road until you get to the summer trailhead. The entire route is very well marked with frequent signs featuring a skiing/hiking bear character, so keep an eye out for those.
From the summer trailhead you switchback onto what is a part of a large ridge which you will follow for the most of the hike. The trail is very obvious even with no tracks at the bottom however the snow will eventually make things indistinguishable, and your best will be to look for the yellow signs with the bears.
Eventually you get to a col between the summit of the ridge you are climbing and the summit of Oshamambedake. Aim for the lowspot and you start the final steep 200m climb to the summit. Tackling this bit can be a bit tricky, the open face to the left is an easier climb however the treed area to the right will provide more protection from wind. Take care not to get close to the edges of the cornices to the left. You may need crampons depending on the conditions for this portion.
The peak has two high points and the one to the south is the summit. Once at the top the views are fantastic. While most of the mountains are fairly indistinguishable in summer, they are quite impressive in winter, in particular Toshibetsudake to the west. You can see the Pacific Ocean to the east and the Sea of Japan to the west and the Niseko Range and Mount Yotei to the northeast.
Coming down, it is possible to go straight down the big bowl directly below the summit if conditions allow (deadly avalanche terrain though) but skiing down the large ridge to the east from the summit is probably a safer bet. Unfortunately both portions were sheets of ice when I climbed and I ended up following the ridge to the southeast a bit to drop in.
You will eventually end up in the bottom where the few bowls/gullies funnel into the creek that runs along the bottom portion of the hike. Try to stay on the left side as much as possible and you can eventually get to the summer trailhead without hiking back out, however when in doubt best to put your skins back and climb back up to the ridge on your left side until you find your old up-hill tracks. Probably not a good idea to go all the way to the bottom of the gully in spring. Once back on the road, it’s an easy ski back out to your car, maybe a bit more time-consuming on a snowboard.
Just a heads up there’s no cellular service for most of the hike (mainly in the lower portions) and the mountain doesn’t see much visitors, so make conservative decisions.