Two hundred and twenty million years ago, in the later part of the Triassic Period, South Wales and the Bendricks was a desert; however, life existed here! Footprints of animals preserved in the sandstone and siltstones make the Bendricks one of the best sites in Britain for Triassic Dinosaur prints, and is a Site of Special Scientific Interest.
The Vale of Glamorgan was an area of rocky limestone hills and despite low annual rainfall, torrential rain caused flash floods. These floods created rivers carrying boulders, pebbles, sand, silt and mud down to a large lake or inland sea. The deposits of these flash floods can be seen in the almost flat- lying beds of rock along the shore between Bendrick Rock and Sully Island.
Fine sand-filled cracks in some of the beds, also suggest that these were once wet muds and silts, which dried out and cracked when exposed to the sun.
Further Reading
BBC News –Dinosaur footprint found by girl, four, on Barry beach