In reply to Naomi VR:
If you get the train to Gap, it's about 20km to Ceuse. Hitching is still quite a common way to get around in that part of France - several times I picked up locals when driving down to town - so you could do that, although you'd need to hitch out for food shopping on rest days as well.
The campsite is at the end of the road, so the approach is the same for everyone - an hour's slog up a steep trail on your first day, if you're fit and you stash all your gear at the crag, you can do it in half an hour or so on subsequent days.