Gallt yr Ogof's cliffs are scattered around two different aspects of the mountain. The routes vary from low-angled slabs to very steep extremes.
Approach using a small footpath west of the Helyg hut, or over a small bridge from the campsite and parking area at Gwern y Gof Isaf (SH685601).
For Skyline Buttress, the best approach is to walk uphill from Gwern Gof Isaf between the back of Craig Caseg Fraith and the fence line, until you meet another fence running perpendicular to it. Cross the stile, turn left towards the stream, and follow the fence uphill to a point where it kinks away left at a levelling. By now you have picked up a faint path which weaves through the heather onto the ridgeline of Gallt yr Ogof. Skyline Buttress soon comes into view.