Geograph - photograph every grid square

The promontory at Carreg y groes is mantled by glacio-fluvial gravels overlying silts and muds. This complex package of sediments is evidence of meltwaters running in the Conwy Valley in early post-glacial times when the topography was complicated by stagnant and melting ice and sea level somewhat different to that of today. The little beach is a product of modern erosion of these gravels, which also contain cobbles and small boulders that indicate the high energy of flows when they were deposited.