Planning to tick em both off tomorrow as they're long overdue, before I'm knee deep in nappies and short on opportunity. Anybody got postcodes for the trail heads please, the one on mbwales.com is for Bets y Coed centre I think. There's directions but I'm too lazy / incompetent to follow them and would rather follow Tom Tom. Ta.

Go on streetmap.co.uk, postion the arrow on the map and click the text at the bottom of the map saying something like "convert to co-ordinates", that gives you the post code.

don't know if the postcode would get you very close
for penmachno grid ref : SH7867849844 (LL24 0YP)
for the Marin grid ref : SH7896860942 (LL27 0HX)