You didn't come all this way just to climb in California did you? This quarry has some long, serious two-pitch routes. The huge bank of tottering scree at the back gives this area an almost Alpine feeling!
California is not obviously visible from the main public path that runs from the parking area by the Dinorwig bus turnaround. At the back right-hand side of Dali's Hole (10 minutes walk from the parking) a track leads up across scree to a tunnel entrance. Through this (mind your head) - all very Indiana Jones - to emerge in a vast, hidden ampitheatre.