This 285m-high dam in Val d'Hérémence, 28km south of Sion, is a hydraulic marvel. From its base, it’s a 45-minute hike or swift cable-car ride (departures every 10 minutes) to the top. Before jumping aboard, book yourself a 1¼-hour tour of the dam at the information point.

Collecting the meltwater of 35 glaciers, weighing 15 million tonnes and supplying a fifth of Switzerland’s energy, the dam impresses with both its scale and statistics.