This is a either a short walk from Grand Rats (green), or a longer 700m elevation gain hike from the valley floor below, just north of Voreppe (red).
I did it on the 5th April, once the worst of the snow had cleared to >1200m. The harder route from the valley floor looks pretty steep on the map, and turned out to be pretty steep. It had also been recently repaired - with new steps in places, and a new surface of dirt. The lack of leaf litter on the path, and the fresh dirt made it pretty slippy, but manageable on the way up (with hiking poles and good boots). I decided to take an alternative route on the way down (yellow). The total route came out at 12km, 4.5hrs.
On road parking is available as per the map below, or in Voreppe.
There is a hiking wall somewhere in the vicinity of the summit, but I didn’t spot it.