There are basically 3 different ways to climb Gross Muttenhorn by ski. Most skiers start from Furkapass. I think this is a bad choice, for you have a long horitontal path to start with. In the morning it is usually icy and when coming back, this horizontal piece is a bore. If I decide on skis, I want to ski down and not walk horizontally. I can only recommend this route at noon after having climbed Galenstock etc. and want to spend the afternoon in the mountains.
If you drive your car from east (Goeschenen on the Gotthard-autobahn), chose a day shortly after opening the Furka road. Cross the pass and park your car at Muttbach (Oberalpenstafel, 2047 m). The snow stays there to June.
From Muttbach climb up to the western ridge to pt. 3003 or higher. Leave the skis there and walk up to the summit. Wonderful ski-run back to the car.
If for some reason, because the passroad is still closed, you must ski down from Furka pass (2431 m), do not ski down beyond the old railroad-station Tiefenbach (1845 m), then walk along the path to pt. 1861 m (or higher) and ski or walk down to Realp. You might be tempted by the nice snow to follow the old rail track. It will be hell!
Avalanche detector. No rope, no crampons.
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