For an arduous yet gratifying tour of the Alps, look no further than the Haute Route. This ultimate Alpine adventure—beginning in Chamonix, France and ending in Zermatt, Switzerland—can be undertaken either on foot (which takes 12 days) or on skis (which takes seven). In summer, the route is accessible to any hiker in good physical condition but, in winter, it gets much more difficult and requires ski-touring equipment to tackle. During the journey, days are spent traversing vast trails, descending slopes, and navigating glaciers. At night, guests sleep in various Alpine huts, scattered among the towering mountains. When it comes to ski touring, it’s simply the greatest experience on earth.