The Col de la Mine de Fer and Lac de Crop loop from Pré Marcel

By car: on leaving Villard-Bonnot via the D523 heading north, take the D290 towards Sainte-Agnès. After Sainte-Agnès, join the D280 and turn left towards the Col des Mouilles. At the pass, leave the D280 towards Allevard and turn right, before the wooden buildings, onto the Route de Pré Marcel. After 850 m, at the junction, follow the road to the right for 2.4 km and, at the Fork in the road, head left into the car park in a shaded meadow.

(S/E) Return to the fork in the road at the car park entrance and turn left onto the forest track (east). Note a track on the right leading uphill in the opposite direction, marked with a hiking sign.

(1) Follow this track towards the Refuge Jean Collet.

(2) At the wide left-hand bend, ignore the old path branching off to the right (south-east).
The IGN map is out of date and this path is still shown as the access route to the refuge.
Following the edge of the woodland, take the bend to the left, continue for 150 m and then turn right. After about 400 m, you’ll reach a junction at a left-hand bend.

(3) Leave the track (north). Take the path on the right (south) which, shortly afterwards, enters the forest for a good two kilometres before rejoining the old path (alt. 1,500 m).

(4) Leave this path on your right and carry on straight ahead. After a few hairpin bends, you’ll reach a junction on a flat stretch (alt. 1,640 m).

(5) At the sign for “Sous le Rafour” (a severed post with no indication). Ignore the path on the left towards “Sous Orionde”. Follow the path on the right (south-west) towards the refuge. After crossing through the forest and a few hairpin bends, you’ll reach an exposed rocky area (alt. 1,800 m) and cross (south) several gullies and steep sections, some of which are secured by cables, before reaching the Jean Collet Refuge (alt. 1,950 m).

(6) Walk past the refuge and continue along the path (south-east) for about a hundred metres until you reach a three-way junction.

(7) Leave the GR®738 on your right towards the Col de la Sitre and the middle path towards Lac Blanc. Follow the^GR®738 on your left towards the Col de la Mine de Fer, which climbs diagonally parallel to the path to the lake. Cross a small hill, then ascend the gently sloping grassy valley floor. At an altitude of around 2,150 m, begin the final ascent via a steep path zigzagging through rocks and scree, eventually reaching the Col de la Mine de Fer (2,400 m).

(8) At the ‘Col de la Mine de Fer’ signpost, descend 50 metres down the opposite side of the pass (north-east) to a junction.

(9) At the second “Col de la Mine de Fer” signpost, leave the GR®738 to the right towards the Pas de la Coche. Continue left along the yellow-marked path towards Lac de Crop. Descend (north-east), passing between a steep slope on the left and a rock face on the right, until you reach a precipice.

(10) Turn left (north-west) and descend the rocky terraces via two hairpin bends.

(11) Cross a scree slope, then a field of large boulders (west). Do not attempt to head straight down towards the lake but keep level. After a narrower passage between a cliff and large rocks, gradually turn right (north).

(12) On the path, which remains level, across a wider scree slope, head towards a gap. Once through this, the path becomes more distinct again and, on the scree, resumes its descent in switchbacks towards Lac de Crop (alt. 1,910 m), which it follows along the eastern shore.

(13) Shortly after the end of the lake, you’ll come to vegetation again. Pass through a few hairpin bends in the lake’s headwall and reach a junction (alt. 1,830 m).

(14) Ignore the path on the right leading to the Habert du Ferrouillet. Continue along the path to the left (west-north-west) for about 800 m. Leave the forest and reach a junction (elevation 1,706).

(15) At the sign for “Sous Orionde”, ignore the path on the left towards “Sous le Rafour”. Continue along the path straight ahead towards the Pont de la Betta. After 400 m (alt. 1650 m), it turns sharply to the right, plunging down into the woods. At this bend, look out for a path on the left, behind the hillock and beyond some undulating, overgrown ground, leading into the woods.

(16) Leave the signposted path on the right and take the unmarked path on the left (north-west). Follow this for about 1.2 km until you reach a junction (alt. 1,440 m).

(17) At this junction, you have a choice:
- either take the path on the right, which winds down to the wide track linking the Pont de la Béta on the right. Take this to the left towards Pré Marcel.
- or carry on straight ahead to join the same track further on, as shown on the map; this route through the woods, although overgrown, is more pleasant than the long, monotonous track. Continue along this ascending path for about 300 m to reach a junction in a small clearing (alt. 1,460 m).

(18) Ignore the two paths leading uphill to the left. Follow the small grassy path slightly to the right through a gap in the forest (north-west). After almost 1 km on level ground, you’ll reach a junction (alt. 1,440 m).

(19) Ignore the path leading down to the right. Continue straight ahead for 50 m to reach another junction (alt. 1,430 m). Ignore the path climbing to the left and continue straight ahead along a sunken path. Begin a steep, stony descent (north-west) to join a track bordered by a ditch.

(20) Follow this track to the right (north-east) for 250 m until you reach a hairpin bend to the left (alt. 1,370 m).

(21) Ignore the track on the right coming from the Pont de la Betta and follow the track on the left which, after 1 km, leads to the car park (S/E).

Route map

From (1) to (16): conventional signposting; and from (11) to (12) through the large scree slopes, the path is now clearly marked with yellow markings and numerous cairns.
From (16) to (21): an unmarked path, virtually gone, overgrown with wild vegetation that is reclaiming the area. On this section, the use of a GPS is strongly recommended. Note that routeno. 83522714, entitled “Circular walk from Pré Marcel to the Col de la Mine de Fer, Lac de Crop and Orionde”, is a version of this walk that avoids this section, albeit at the cost of an additional 150 m of elevation gain and a shorter circular loop.

From (21) to (1) – standard signposting

The route is neither high-altitude nor exposed, but remains a mountainous trail through rocky terrain and steep slopes where stamina and physical fitness are required.
Note, however, that there are several gullies and steep sections, some of which are secured by cables, before reaching the Jean Collet Refuge (alt. 1,950 m).