Montagne de Sous-Dîne from Usillon

Updated by the author on 28/07 following a recent walk of the route on 24/07.

• Added a note at point (9) recounting the lightning strike on the Croix de Sous-Dine,
• Added a clarification at the waypoint (2) to make it easier to locate the start of the path,
• Update to the ‘Practical Information’ section: the short, eroded section between points (4) and (5), which had been mentioned, has now been repaired. I have removed the comment.

Start the route from the hamlet of Usillon.

(S/E) Take the Chemin de Landron, heading in particular towards La Plagne and the Col de l’Enclave.

(1) Shortly afterwards, after a few gentle bends and at a signpost, look out for and take a path on the left. Ford the Ruisseau de la Plagne, then follow a path that winds its way uphill in a series of hairpin bends.

(2) When you reach a track, follow it to the left. After a short while, you’ll come to a junction at a place called La Pierre Taillée.

(3) Carry on to the right, towards the viewpoint.

(4) Before long, you’ll reach a very pretty viewpoint. Carry on straight ahead, walking at the foot of the cliffs and then further away from them.

(5) You’ll reach a junction: continue left along the path, heading uphill, with a few steep sections over a short stretch. You’ll reach the Col de l’Enclave just after passing a chalet.

(6) Carry on straight ahead, joining another path further up: follow it to the right. Shortly after passing the beautiful viewpoint at Trou de la Pierre, you’ll reach a junction.

(7) Turn left, towards Sous-Dîne. (Please note: from this point, you are entering a protected area for the black grouse, where you must stay on the marked paths).

(8) Near an unnamed pass, head to the right, following the ascent. The route then continues across a few sections of sharp limestone pavement, through a plateau-like landscape.

(9) The summit, marked by a cross, offers lovely 360-degree views. Retrace your steps back to the Trou de la Pierre junction.

Note: I revisited this spot on 24 July and noticed that the Croix de Sous Dine had been struck by lightning; from what I’ve since read, it appears this happened just before my visit and a new cross is due to be erected on 19 September 2026.

(7) Continue to the left, along the path which first climbs and then descends. You’ll reach the Col de Landron near a chalet.

(10) Carry on to the right, towards Usillon. After a short descent, join another path at the foot of the cliffs.

(11) Turn left. Follow the path for a short while, winding through numerous hairpin bends and over a few steep slopes. At a place called La Plagne, you’ll come to another path.

(12) Continue to the left, following the descent, then return to the starting point (S/E).

You start the route in the hamlet of Usillon at the junction of the Route des Glières (RD55) and the Chemin de Landron (visible on Google Maps), a few metres from a bus stop. Parking spaces nearby are very limited: refer to the locations indicated on OpenStreetMap or park further away at the side of the road.

Sturdy walking boots and walking poles are recommended.

You’ll be passing through a capercaillie conservation area on the Montagne de Sous-Dine, and you must stay on the marked paths.

Please take your rubbish away with you – nature will thank you for it.

Below is a difficulty rating for each section (the route is not uniform):
- Green: fairly straightforward walking with no significant elevation gain or difficulty.
- Blue: slopes and/or elevation changes are more pronounced on a well-marked route.
- Orange: routes presenting some technical difficulties and/or poor route conditions (markings or visibility of the path).
- Red: a difficult route due to significant elevation changes that may require some climbing, in an environment presenting certain hazards.
- Black: a route on a fairly difficult trail and/or involving imminent dangers.
- White: routes through very challenging technical terrain requiring specific equipment.

From (S/E) to (1): Green difficulty
Take the uphill street which continues as a track suitable for vehicles.
Marked with yellow arrows and signposts.

From (1 to (2): Blue difficulty
Follow a reasonably good path with few difficulties.
This section is unmarked.
Alternatively, you can also continue along the signposted track, then carry on straight on at the hamlet of La Plagne; this route is easier, but it is about 400 metres longer.

From (2) to (4): Blue difficulty
The route follows a track suitable for vehicles with a gentle gradient, then continues with a few steep sections. Further up, the route continues along a footpath.
Marked with yellow arrows and signposts.

From (4 to (5): Blue difficulty
The route continues along a path with minimal elevation change (downhill then uphill), running at a distance from the cliffs of the Enclave. Take care when walking near some steep slopes.
Unmarked section.

From (5) to (6): Blue difficulty
The path winds its way up a few steep slopes, then runs along the base of the cliffs before reaching the Col de l’Enclave.
Markings: Yellow Arrows + signposts.

From (6) to (7): Green difficulty
It’s an easy walk along a path over slightly steep slopes.
Markings: Yellow Arrows + signposts.

From (7) to (8): Blue difficulty
Follow an uphill path with no significant difficulties to be encountered.
Signposted with Yellow Arrows and signposts.

From (8) to (9): Blue difficulty
You enter a somewhat ‘wild’ section where you may occasionally lose sight of the path near the sharp limestone pavement.
Markings: Yellow Arrows + signposts.

From (7) to (10): Green difficulty
You follow an easy path that first climbs and then descends.
Markings: Yellow Arrows + signposts.

From (10) to (11): Blue difficulty
The route continues along a path with no significant difficulties to encounter.
Marked with Yellow Arrows and signposts.

From (11) to (12): Blue difficulty
We follow a long stretch of path with a few steep sections.
Marked with Yellow Arrows and signposts.

From (12) to (S/E): Green difficulty
Follow an easy track suitable for vehicles, which takes you back to the starting point.
Marked with Yellow Arrows and signposts.

• Montagne de Sous-Dîne: read the Wikipedia article
• Ibex: you may well spot some during the hike.