Park at Tanygrisiau at base of track into Cwmorthin, walk up hill, about 300m (then it levels out), you arrive at Cwmorthin Lake, with the Barracks on your left, walk past them to the left of the lake, and you have slate fences, a ruined chapel, continue walking, you have more ruins and the quarry amnagers house across the field. You then have option of the steep climb up into Rhosydd. Well worth it, and if you go through Rhosydd there are some dramtic views out towards the coast. My advice, stop messing about in the usual tourist traps!!!