From Le Grand Bornand, head up towards Chinaillon. At Les Nants, take a narrow road on the left, towards the hamlet of Le Mont. The car park is at the end of this road.
(S/E) From the car park, follow a forest track suitable for vehicles on the right-hand side, as you approach. Take a few bends before reaching the junction with another forest track.
(1) Carry on straight ahead, passing the turn-off for Sur le Mont on your right. Continue uphill until you reach the junction marked by the ‘Cotagne’ sign.
(2) From there, take the path that climbs to the right towards the north, through the forest, towards Les Mouilles. Further up, pass the turn-off to the hamlet in question on your right, cross a mountain pasture, then cross through a wooded area again.
(3) Once at the edge of the woodland, go through the small gate and immediately leave the path that descends towards La Culaz. Head left, due north: there is no longer a path, so you’ll need to follow a sloping rock and climb towards a clearing in the woodland. You’ll soon rejoin the path that climbs up from La Culaz: this path isn’t shown on the IGN map but is marked on OSM. There’s an old tree trunk lying across the path, which will help you find your way on the descent.
(4) Turn left onto this well-marked path, which initially heads south-east, then due north. After climbing up a scree slope, you’ll reach an unnamed pass.
(5) Turn right, heading north, and reach the main summit of Les Charmieux, marked by a cross.
(6) Descend back to the pass. From there, it is possible to continue the descent via the ascent route. However, it is well worth climbing to the little-visited secondary summit. To do this, head south-east, finding the best route through a small rocky outcrop which can be crossed without difficulty.
(7) From the secondary summit, return to the pass.
(5) Turn right and follow the path you took on the way up, in the opposite direction, until you reach the fallen tree trunk across the path.
(4) Turn right off the path.
(3) Turn right again and follow the ascent route back down to return to the car park (S/E).