The summit is very similar to that of Pen y Fan: flat and anvil-shaped. It is similarly formed from the relatively erosion-resistant Devonian age sandstones from the Upper Old Red Sandstone known as the Plateau Beds.
Similar in shape to Pen y Fan, the summit is a flat, anvil-like formation. Like it, it is constructed from resistant Devonian-age sandstones of the Upper Old Red Sandstone, specifically the Plateau Beds.