Tour du Val d’Hérens: Grande Dixence dam to Arolla (stage 2)

The 2nd stage of the Tour du Val d’Hérens leads from the world’s tallest dam along Switzerland’s largest reservoir to the foot of glacier-strewn summits – and over a pass that has become sporting legend.

The second leg of the 5-stage Tour du Val d’Hérens links two side valleys: the Val d’Hérémence and the Val d’Arolla. The first part of the hike is a flattish walk the length of the Lac des Dix. A steep climb leads up to the Col de Riedmatten, which links the two valleys. The final stretch of hike is a steady descent to the village of Arolla. The hike starts at the crest of the Grande Dixence, the world’s tallest gravity dam. From here it leads along the western shore of the Lac des Dix: Switzerland’s largest artificial reservoir, with a capacity of 400 billion litres of water. The setting is spectacular, with a parade of snow-capped peaks, draped with glaciers, forming a sparkling backdrop beyond the lake. The trail climbs above one of the glaciers to a pass made famous by the world’s toughest ski mountaineering race. The Patrouille des Glaciers, held every other spring, sees teams of three race from Zermatt across the mountains and glaciers to Verbier, and has won a reputation as the world’s toughest team competition. The steep and narrow climb to the Col de Riedmatten (2,918 m) is one of the contest’s great challenges – although the ascent in summer should not pose problems for experienced mountain hikers. From here, the trail leads steadily down to Arolla in the neighbouring valley. Before starting the hike, if time permits, it is worth calling in at the visitor centre at the foot of the dam to learn about the region’s geology and wildlife. The centre also reveals some of the secrets of the pioneering Grande Dixence complex, which unites a vast network of reservoirs, underground tunnels, pumping stations and power plants to form Switzerland’s largest hydro plant. Highlights: Grande Dixence – world’s largest gravity dam, visitor centre (free admission) and cable car Lac des Dix – flat trail along Switzerland’s largest reservoir, framed by snowy peaks Col de Riedmatten – dramatic climb to an iconic mountain pass

Offerte disponibili

Il tuo alloggio in un clic

Nel nostro negozio online, troverete una vasta scelta di offerte in tutto il cantone e potrete facilmente prenotare l'alloggio di vostra scelta.

Turn-by-turn directions

The second stage of the Tour du Val d’Hérens starts at the top of the dam, and follows the western shore of the lake – initially through a sequence of tunnels, then higher up across open meadows. At the far end of the reservoir, the trail leads along the short southern shore before embarking on a steep climb up to the Col de Riedmatten (2,918 m). Alternatively, cross the ridge about 200 m further south at the Pas de Chèvres (2,854 m), famous for its sequence of ladders up an exposed rock face: a sure foot and a good head for heights are required. The two paths merge again on the eastern side of the ridge; the trail then descends steadily to Arolla.

To reach the start of the walk from the foot of the dam (bus stop, visitor centre), either ride up to the crest by cable car or walk up (allow 45 minutes).

Options for overnight accommodation before tackling the walk: Hôtel du Barrage (at the foot of the dam) or the Cabane de Prafleuri (about 1 h 30 min on foot from the crest).

Start: Grande Dixence dam (2147 m)
Destination: Arolla (2011 m)

Author's recommendation

Before starting the walk, call in at the Grande Dixence visitor centre (free entry) to find out about the dam, reservoir and local wildlife.

Technical information

  • Altitude

    2923 m 2011 m

  • Ascent

    891 m

  • Descent

    1028 m

  • Technique

    Bewertung: 5 .0 von 5.0 Punkten

  • Stamina

    Bewertung: 5 .0 von 5.0 Punkten

  • Expérience

    Bewertung: 6 von 5.0 Punkten

  • Landscape

    Bewertung: 6 .0 von 5.0 Punkten

Public transport

Train to Sion, then postal bus to Grande Dixence dam. At end of walk, postal bus from Arolla to Sion (change at Les Haudères). Find full timetable information at


A9 motorway, exit 27 (Sion-Est), follow signs for Vex/Hérémence/Grande Dixence.


At Grande Dixence. However, for a day trip, it makes more sense to park lower down the valley – e.g. at Vex – and to travel by postal bus to the start of the walk and back from the finish.


We recommend: 

  • good footwear
  • clothing suitable for the weather: always carry a waterproof jacket
  • hat or cap
  • sunscreen
  • bottle for water
  • picnic
  • camera
  • binoculars (optional)
  • hiking poles (optional)
  • printout of this hike (click «Print» icon, to download)  

For certain walks:

  • Swimwear

Safety information

Use of the trails and the information on this website is at hikers’ own risk. Local conditions may entail changes to routes. Valais/Wallis Promotion accepts no liability for the accuracy and completeness of information on this website.

For all hikes:

  • Bring a map. Download full description of this route including large-scale map by clicking on «Print» icon, top right of this page.
  • Use marked trails only, and observe all signposting – for your own safety, to safeguard grazing animals and to avoid disturbing wildlife.
  • Close gates after passing through.
  • Please be considerate to other trail users, and to the plants and animals.
  • Do not leave any waste in nature.

For mountain hikes:

  • Take extra care protecting yourself from the sun at altitude. UV radiation can be exceptionally strong, even in cloudy weather.
  • Plan hike carefully: take into consideration fitness level of each participant, weather forecast and season.
  • Weather conditions can change quickly in the mountains, without warning. Appropriate clothing is therefore essential, along with adequate supplies of food and water. In uncertain weather, turn back in good time.

For high-altitude hikes:

  • Inform others of the route you plan to take. Whenever possible, avoid going alone.
  • Do not venture onto glaciers without a mountain guide.
  • Take note of the warning signs that point out the constant danger in river beds and along watercourses below dams and reservoirs: water levels may rise rapidly without warning.


The tourist offices in Val d'Hérens have got brochures and information material about hiking in the region.


SwissTopo maps 1:25’000: 1326 Rosablanche / 1346 Chanrion / 1347 Matterhorn