To be honest, although I had heard of it, I didn't realise where it was until last week. I was planning a loop of the Carnedd this Saturday but now realising where it is I am going to do Crib Lem instead.
It seems pretty straight forward, but any advice from those who have done it?
My understanding is as you are facing the large wall (Llech Ddu?), follow the right hand side up into the Cwm, then almost back on yourself following a shoulder until you are on the ridge itself, then there is only up!
The hardest part looks to be finding parking in Gerlan.