In reply to Red Rover:
Hi
I did some lovely walk's from Cwm Eigiau area recently, from the car park (SH 731 663). My route followed the track into Dulyn Reservoir, there is a Bothy there, a good place for a cuppa, then retraced steps to SH 711 659 where you can get up to 735 high point (SH 713 655) I came around to SH 698 646 (just up from Gledrffordd) and dropped down into Cwm Eigiau, below Craig yr Ysfa, and followed the main track back to the cars. That was a good day out.
Perhaps, depending on your group though, and how they are feeling, at SH 725 666 you can leave the main track there and pass the ruins of Maeneira, then on up to Pen y Castell, and just return to the car park the way you came. Either way its a good area to explore.
Jason