This question would have been obscure enough, IMHO, even without the inaccuracies and ambiguities.
The Inferno is an annual ski race that has taken place in the Swiss village of Mürren (not Morren) since 1928. It runs for 15.8 kilometres (9.8 miles) from the summit of the Schilthorn (the mountain that overlooks the village), at 2,970 metres (9,744 ft), to Lauterbrunnen (the larger town further down the valley).
I know next to nothing about skiing, but the words "ski run" in the question suggest to me some sort of man–made edifice (in the manner of the Cresta Run – which I do know, by the way, is for toboggans and not skis). As stated above, the Inferno is no such thing; it's an annual event.
Mürren lies in the shadow (metaphorically at least) of the three iconic mountains of the Bernese Overland: the Jungfrau, the Mönch and the Eiger.
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