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The first decision on the Niesen is where to start. From Mülenen, the summit means roughly 1,650 metres of climbing. It is a hard day on foot.
Taking the funicular to Schwandegg cuts out the lower climb, though the upper paths still call for steady footing and proper hiking shoes.
Choose your route from the operator’s map and check the last train down before setting off. Carry food, water and warm layers; walking down adds a substantial descent. Follow the hiking paths. The staircase alongside the railway is normally closed to visitors.