In reply to iccle_bully:
Thank you for that. We visited today, after a brief stop into the local tourist info centre. They gave us a generic walking brochure which showed the location.
We did find the crag, but I'm sorry to say there wasn't a lot of bouldering there! Fortunately it's a nice spot for lunch....
The map referred to which lead us there, is a French IGN map. I've had a few dodgy French maps of late, so this might be another one!
Thanks again.