This route marks a geocaching and photography trek I undertook a couple of months back. I was planning to take the full route to the top of the Grande Sure, however the trek to the Cul de Lampe and the meadow at the top took long enough, so we didn't take the extension.
I've sketched the route taken in green, and the optional extension (not taken) in blue.
The trek starts after a long, uneven track (somewhat rough, best suited to 4x4s) from a car park at around 790m. It climbs steeply up a forested hillside to the Cul de Lampe at around 1500m, and then onwards up to a very picturesque alpine meadow. We continued up to Col de la Charmille, and then returned after a short ridge walk, via the summit at 1627m.
If you take the extension to le Grande Sure, the summit will take you up to 1920m making this a substantial 1200m climb.