Ascent
We have a comfortable time. Although the road is not yet open until the hotel, we can still cover a few kilometers by car from Gadmen. It doesn't matter where you park your car - just follow the pass road to the Hotel Steigletscher. After the Hotel Steigletscher, you soon turn right and head into the valley towards Steisee. Here, however, you do not head towards the lake, but along the ridge to the west (right) of the lake in the direction of Chuüöbärgli. At this point at the latest, it becomes clear that the orientation is nice and easy.
At around 2,200 m, you will find yourself below a small steep slope on the Steigletscher (which has probably largely melted away here). Finding the route on the glacier is also easy: simply follow the terrain as closely as possible and always look for the flattest line on the glacier. At approx. 2,400 m, turn right and climb up a somewhat steeper and more crevassed slope, which becomes more comfortable again at approx. 2,600 m. Then head either towards the Tierbergli hut or directly to the north-western flank of the Gwächtenhorn (3,420 m). From here, the route does not ascent the flank, but continues below through a moderately steep hollow and less steep firn slopes in the direction of Sustenlimi (3,089 m). From there, climb towards the NNW and Sustenhorn. The last few meters along the Sustenhorn south ridge can be so bare that it is worth taking off your skis for a short time. Otherwise, you can reach the summit on skis without any major difficulties.
The descent is largely the same as the ascent.