Cors Caron’s story begins at the end of the last ice age. At its peak, around 25,000-20,000 years ago, large areas of Wales, including the Cambrian Mountains, were covered by ice. In many valleys in north and mid Wales, glaciers flowed like rivers of ice from the uplands. As temperatures warmed at the end of the ice age, the glaciers started to melt leaving behind ridge-shaped mounds of sediment, boulders, gravel, sand, silt, and clay, called moraines. These moraines mark the former location of glacier fronts, known as snouts. Although not immediately clear in the landscape, a moraine roughly ten metres tall can be found near Pont Einion’s historic bridge, southwest of Cors Caron. Scientific research suggests that the glacier had melted back to this point by about 15,000 years ago. The moraine formed around this time and afterwards acted as a dam, behind which melting water from the retreating glacier and snowfall collected forming a lake. Over time, the landscape developed because of continued plant growth, transforming the open lake with plant life on its margins into a swampy woodland. This swampy woodland then transformed into the peat bog we now know as Cors Caron.
