Le Grand Som from the Col du Cucheron

de fr

This is definitely the easiest and shortest way to climb the Grand Som.

Caution for those prone to vertigo: between (2) and (3), the walk becomes a climb in places. The passages are often narrow and can be daunting.

Details

n°760186
Creation:
Last update:
Last review:
  • Walking
    Activity: Walking
  • ↔
    Distance: 8.74 km
  • ◔
    Average duration: 5h 00 
  • ▲
    Difficulty: Difficult
  • ⚐
    Back to start: Yes
  • ↗
    Ascent: + 881 m
  • ↘
    Descent: - 880 m
  • ▲
    Highest point: 2,019 m
  • ▼
    Lowest point: 1,138 m
Downloads
Open in the mobile app
Download GPX GPX
Download PDF PDF

Photos

Racapé
via ferrata
From the summit in September
Col des Aures

Description of the walk

Access: you can reach the starting point either from Saint-Pierre de Chartreuse or Saint-Pierre d'Entremont. You will easily find a place to park at the pass.

(S/E) Cross the departmental road and take the small road that climbs towards the Col des Aures and the Grand Som. You will soon come to a first intersection.

(1) Take the path on the left that climbs into the forest. The slope is quite steep at first but the path quickly becomes easier. Be careful, some sections are not very wide.
Follow the yellow markings to the pass, ignoring the paths on the left. The trail is pleasant, the slope is ideal and the 500m elevation gain is very easy. From time to time, gaps in the forest will allow you to see the Scia and its refuge.

(2) At the Col des Aures, you will emerge from the forest.
Continue left on the stony path that climbs in front of you. This section is much more difficult as the passages are often narrow and can be daunting. In places, walking turns into climbing. Fortunately, there are cables to secure you.
Join the junction with the path that leads to La Suiffière and Saint-Pierre d'Entremont.

(3) Keep right towards the summit. You will quickly leave the stony path and enter an alpine meadow.
The cross is in front of you. You still have almost 100 metres to climb. The slope is steep, so take your time; you'll soon be at the summit.

(4) Once you reach the cross, you will be rewarded with a magnificent 360° view (weather permitting). You can see the Vercors, the Chartreuse, Belledonne and more if the view is clear. Take a moment to catch your breath, then begin the descent to the Col des Aures. Take extra care here as it is easy to slip.

(2) The hardest part is over, you can breathe easy. After one last look at the Grand Som, take the small path opposite for the return journey. It is not signposted and not very visible. Climb up through the pine trees towards the ridge. You will soon reach a flat area. From there, follow the path for 500 to 600 metres until you reach the next crossroads.

(5) Turn right. The path is pleasant but be careful of the slope and the risk of slipping.
Shortly before the next point, the slope becomes steeper and the path less visible. After this rapid descent, you will come out onto a fairly wide path.

(6) Cross it and continue downhill to the Cucheron barns.

(1) You are almost there. Turn left and, after 100m, you will find the car park (S/E).

Waypoints

  1. S/E : km 0 - alt. 1,139 m - Col du Cucheron
  2. 1 : km 0.13 - alt. 1,153 m - Crossroads of the loop. Pass along the - Couzon (cours d'eau) - Affluent du Guier
  3. 2 : km 3.04 - alt. 1,635 m - Col des Aures (1639m)
  4. 3 : km 3.58 - alt. 1,816 m - At the crossroads, turn right towards St Pierre de Chartreuse.
  5. 4 : km 4.07 - alt. 2,019 m - The cross at - Grand Som (2026m)
  6. 5 : km 5.97 - alt. 1,557 m - Cucheron/Les Reys crossroads, on the right
  7. 6 : km 7.41 - alt. 1,332 m - Crossroads
  8. S/E : km 8.74 - alt. 1,139 m - Col du Cucheron

Reviews and comments

4.7 / 5
Based on 62 reviews
Reliability of the description
4.7 / 5
Ease of following the route
4.6 / 5
Route interest
4.8 / 5
dibbeguin
dibbeguin

Overall rating : 5 / 5

Date of your route : Oct 06, 2025
Reliability of the description : ★★★★★ Very good
Ease of following the route : ★★★★★ Very good
Route interest : ★★★★★ Very good
Very busy route : Yes

Very beautiful hike. Excellent description that perfectly describes the route.

Machine-translated

Courgoulet
Courgoulet

Overall rating : 4.7 / 5

Date of your route : Sep 29, 2025
Reliability of the description : ★★★★☆ Good
Ease of following the route : ★★★★★ Very good
Route interest : ★★★★★ Very good
Very busy route : Yes

In my opinion, it is important to emphasise the section at the end of the forest, which is dizzying and involves a significant amount of small climbing that can be complicated, especially on the descent.

Machine-translated

User 26995616

Overall rating : 4.3 / 5

Date of your route : Aug 05, 2025
Reliability of the description : ★★★★★ Very good
Ease of following the route : ★★★★☆ Good
Route interest : ★★★★☆ Good
Very busy route : No

I just finished the loop.
The hike is truly magnificent, alternating between the woods (at the start and end of the hike) and the ridges (ascent and descent of the Grand Som).
The description is very clear and precise; there is a slight difficulty in finding the trail in the woods after reaching the pass on the way back from the Grand Som and seeing the n5 junction.
A difficult hike but entirely doable if you're in good physical condition.

Enjoy your walk!

Machine-translated

User 3696556

Overall rating : 4.3 / 5

Date of your route : Jul 19, 2025
Reliability of the description : ★★★★★ Very good
Ease of following the route : ★★★★☆ Good
Route interest : ★★★★☆ Good
Very busy route : No

The advantage of starting from the Col du Cucheron is that the climb is gentle under the cover of the forest, which is pleasant in hot weather, and you don't feel the elevation gain.

Machine-translated

DanielANDRE
DanielANDRE

Overall rating : 5 / 5

Date of your route : Jul 12, 2025
Reliability of the description : ★★★★★ Very good
Ease of following the route : ★★★★★ Very good
Route interest : ★★★★★ Very good
Very busy route : Yes

Very beautiful hike despite the crowds at the summit
Splendid view from the Vercors to Mont Blanc

Machine-translated

User 18657150

Overall rating : 4.7 / 5

Date of your route : Jul 09, 2025
Reliability of the description : ★★★★★ Very good
Ease of following the route : ★★★★☆ Good
Route interest : ★★★★★ Very good
Very busy route : No

A beautiful hike with exceptional views from the Col des Aures to the summit.
The hike is in two stages: from the Col du Cucheron to the Col des Aures along a very pleasant shaded path. Do not follow the route marked on the map exactly, as it is not the same as the path. The path marked with a yellow line is the correct route.

The second part is a very stony climb from the Col des Aures to the cross. It is over pebbles and rocks with cables, then you arrive at a large, magnificent meadow leading to the cross.

This route may be considered very difficult for inexperienced hikers or those prone to vertigo. There is a risk of falling near the cables, so do not attempt this hike if there is a risk of thunderstorms, and avoid it if the sunny path is wet, as the descent could become very dangerous.
Having done it without children, I can confirm that I would not take my 10-year-olds (who are experienced hikers) on this hike, perhaps in a few years when they are 13 or 14.

The return via the ridge path is great and allows you to make a loop. I had to use GPS to find the entrance and point 5, but otherwise the path is very visible until the Petit Cucheron pass.

It took us 5 hours and 15 minutes to complete the loop at a steady pace. A beautiful day

Machine-translated

User 19003251

Overall rating : 4.7 / 5

Date of your route : Jun 04, 2025
Reliability of the description : ★★★★★ Very good
Ease of following the route : ★★★★★ Very good
Route interest : ★★★★☆ Good
Very busy route : No

Very difficult walk over the last 500 metres. Extraordinary views. To be done in good weather with no wind or risk of thunderstorms. We did this walk when we were 74 and 72 years old.

Machine-translated

Juli
Juli

Overall rating : 5 / 5

Date of your route : Dec 02, 2024
Reliability of the description : ★★★★★ Very good
Ease of following the route : ★★★★★ Very good
Route interest : ★★★★★ Very good
Very busy route : Yes

A beautiful walk, interesting, sunny, perfect!

Machine-translated

Anibac
Anibac

Overall rating : 5 / 5

Date of your route : Nov 17, 2024
Reliability of the description : ★★★★★ Very good
Ease of following the route : ★★★★★ Very good
Route interest : ★★★★★ Very good
Very busy route : Yes

The climb to the foot of the large hill in the woods is steady and very pleasant. The steep section requires caution and attention but is accessible, especially with the handrail. However, there are also some tricky spots where you need to stay alert. The last section is challenging but the cross encourages us to keep going, as does the large number of hikers.
The 360° panorama is superb, as is the view down to the monastery.
Special mention for the return route, which I chose despite some criticism. Well, it was perfect for me because the path is not uneven, so you can take it easy without pushing yourself. Nevertheless, I had to use my GPS twice (once at point 5 and a second time before the junction between points 5 and 6). If I do this hike again, I will choose the suggested direction and also the loop. Thank you very much for this itinerary!

Machine-translated

Bernard Delon
Bernard Delon

Overall rating : 4.7 / 5

Date of your route : Nov 04, 2024
Reliability of the description : ★★★★★ Very good
Ease of following the route : ★★★★☆ Good
Route interest : ★★★★★ Very good
Very busy route : Yes

The route begins in the woods. From the Col des Aures, follow a well-marked trail.
Cross the rocky ridge with a cable. Risk on this section: 5/5, no falling!
Very steep climb on the last kilometre.
Return via the Crête des Aures, which is very quiet.
Needless to say, the view is magnificent.

Machine-translated

Isabelle Cloux
Isabelle Cloux

Overall rating : 4.7 / 5

Date of your route : Aug 14, 2024
Reliability of the description : ★★★★★ Very good
Ease of following the route : ★★★★☆ Good
Route interest : ★★★★★ Very good
Very busy route : No

A very beautiful route, busy on the way there, but the return journey from the Col des Aures is completely deserted, as people prefer to go back down the same way they came.
I really enjoyed this different return route, which I think gives the circuit a slightly wilder feel.
Of course, the view from the summit is magnificent and spectacular, well worth the effort of climbing a few rocks, but for those who are used to hiking on rocks and at altitude, it's no problem, as the steep sections are equipped.

Machine-translated

Jeffrey38
Jeffrey38
• Edited:

Overall rating : 4 / 5

Date of your route : Sep 15, 2024
Reliability of the description : ★★★★☆ Good
Ease of following the route : ★★★★☆ Good
Route interest : ★★★★☆ Good
Very busy route : Yes

Hike with a magnificent 360° panorama at the summit.

The only difficulty or apprehension may lie in the cable crossing, where you are relatively close to the void.
It is not insurmountable, but depending on the person, it can be off-putting.
Completed in 3 hours and 40 minutes at a good pace.

Machine-translated

Thierry38
Thierry38
• Edited:

Overall rating : 4.7 / 5

Date of your route : Aug 16, 2024
Reliability of the description : ★★★★☆ Good
Ease of following the route : ★★★★★ Very good
Route interest : ★★★★★ Very good
Very busy route : No

A beautiful hike that takes you to one of the most famous peaks in the Chartreuse Mountains. Unfortunately, the view at the top was somewhat limited due to heavy cloud cover. The Racapé passage is not recommended for those prone to vertigo. This passage is challenging but remains very accessible for those with mountain walking experience. Good shoes are nevertheless essential, especially for the descent. The last part of the climb up to the mountain pasture is steep and requires you to take your time. The return via the Crête des Aures is very pleasant despite a very steep slope at the end of the route. The only slight downside is the distance indicated. According to the GPS app launched at the start, the distance is closer to 12 km than the 8.7 km indicated. However, this does not detract from the beauty of the route. Thank you to the route planner!

Machine-translated

mariebleuet
mariebleuet

Overall rating : 4.7 / 5

Date of your route : Aug 09, 2024
Reliability of the description : ★★★★★ Very good
Ease of following the route : ★★★★★ Very good
Route interest : ★★★★☆ Good
Very busy route : No

Clear explanations about the route, particularly regarding difficulties on the climb and the risk of falling on the descent.

Machine-translated

pepinet
pepinet

Overall rating : 4.7 / 5

Date of your route : Aug 02, 2024
Reliability of the description : ★★★★★ Very good
Ease of following the route : ★★★★★ Very good
Route interest : ★★★★☆ Good
Very busy route : No

The climb up through the forest is easy, but beyond that it gets more difficult, although the cables make it manageable. The mountain pasture is very steep. The descent is much trickier, as the rocks are slippery even when dry. The return via the ridge is very shady and pleasant, with a gentle descent except towards the end, where there are a few very steep sections, which are tough going given how tired you are. A beautiful, challenging hike.

Machine-translated

Other walks in the area

Walking The Grand Som circular loop via the Col des Aures and Col de Mauvernay passes

Association / Club / Walk leader
↔13.32 km ↗+1,187 m ↘-1,187 m ◔7h 10 ▲Difficult
⚑Departure from Saint-Pierre-de-Chartreuse (Isère)
This extensive circular route will take you to one of the most legendary peaks in Chartreuse. Technical passages, magnificent views of the massif and the Chartreuse monastery, wild trails: it has it all!

Walking The Grand Som circular loop via the Suiffière ridge and the Chemin Racapé

Visorando member
Le Grand Som en boucle par l'arête de la Suiffière et le Chemin Racapé
↔8.88 km ↗+1,054 m ↘-1,050 m ◔5 hrs ▲Very difficult
⚑Departure from Saint-Pierre-de-Chartreuse (Isère)
This is a classic circular route, both fun and demanding, but without any major difficulties. It was found almost unchanged in Chartreuse - Vercors: Les randonnées du vertige by Pascal Sombardier. As this cult book is now out of print and virtually impossible to find, I think it is worth mentioning it here, with what I hope is a clear description of the route. This circular path is strongly discouraged for people who are afraid of heights or who are unsure of themselves on steep terrain. It is therefore not suitable for children either. See the Practical Information section. Rated very difficult from (3) to (4) and then to (5).

Walking Crossing the Lances de Malissard ridges

Visorando member
Traversée des crêtes des Lances de Malissard
↔16.47 km ↗+1,472 m ↘-1,474 m ◔10 hrs ▲Extremely difficult
⚑Departure from Isère
To reach the Fontanieu chimney, the classic route climbs through the forest on the western slope of the Mallissard valley. It is difficult to find your way here due to a maze of forest paths created by logging. In addition, the maps are often out of date.The proposed hike avoids this wooded valley and passes through a little-used area where the route is easy to follow with very few intersections. It consists of a single track, climbing up a valley to the Col de Fontanieu. However, this adds 2 km to the hike and 50 m to the elevation gain. From the pass, the trail climbs to the foot of the cliff and follows it to reach the Fontanieu chimney. Then there is a long aerial traverse followed by a ridge crossing. From the summit of the Lance Sud de Malissard, the return is via the Col de Bellefont and the Col de la Saulce. 4/12/2023: Some sections may be closed (see practical information).

Walking The Lances de Malissard from Les Essarts

Visorando member
Les Lances de Malissard depuis Les Essarts
↔10.63 km ↗+790 m ↘-798 m ◔5h 20 ▲Difficult
⚑Departure from Saint-Pierre-de-Chartreuse (Isère)
This route has the least elevation gain for climbing one of the four peaks over 2,000 m in the Chartreuse. Magnificent view of the back of the Dent de Crolles, the north of the Chartreuse and, on the other side, the majestic Mont Blanc.

Walking Col de Bovinant via the 120 hairpin bends and Col du Frêt

Visorando member
Col de Bovinant par les 120 lacets et col du Frêt
↔7.40 km ↗+782 m ↘-785 m ◔4h 20 ▲Moderate
⚑Departure from Saint-Pierre-d'Entremont (Isère)
A beautiful hike in Chartreuse that follows the route of the 120 hairpin bends to reach the Col du Frêt, before turning onto the Col de Bovinant. In the second half of June, the flora is in full bloom: St Bruno's lilies, martagon lilies, columbines, anemones, gentians...

Walking Le Grand Som via the Col du Frêt, Le Racapé and the Crête des Aures

Visorando member
Le Grand Som par le col du Frêt, le Racapé et la crête des Aures
↔10.84 km ↗+1,078 m ↘-1,071 m ◔6h 10 ▲Difficult
⚑Departure from Saint-Pierre-d'Entremont (Isère)
A wilder approach to this iconic peak of the Grande Chartreuse, which will require some route finding to reach the starting point.

Walking Tour of the Saint-Pierre-de-Chartreuse valley

Visorando member
Tour de la vallée de Saint-Pierre-de-Chartreuse
↔13.11 km ↗+294 m ↘-291 m ◔4h 35 ▲Moderate
⚑Departure from Saint-Pierre-de-Chartreuse (Isère)
Leave the village and walk around the valley, discovering the main peaks as you go: Charmant Som, Chamechaude, Dent de Crolles, Scia and Grand Som. You will also pass through several Carthusian hamlets.

Walking Charming Som via the Bérard ridge

Association / Club / Walk leader
Charmant Som par l'arête de Bérard
↔14.80 km ↗+1,412 m ↘-1,405 m ◔6 hrs ▲Very difficult
⚑Departure from Saint-Pierre-de-Chartreuse (Isère)
A wonderful circular hike with no major difficulties, except for the length and elevation gain! After the point (3), the trail becomes more technical (especially in rainy or snowy weather).

For more walks, use our search engine .

The GPS track and description are the property of this route's author. Please do not copy them without permission.