Читать книгу The Ceredigion and Snowdonia Coast Paths. The Wales Coast Path from Porthmadog to St Dogmaels онлайн

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An outcrop of Aberystwyth Grits at Allt-wen, south of Aberystwyth (Day 9)

South of Tal-y-bont to Llanaber, the path runs over much younger clays, silts, sands and gravels formed a mere 55 to five million years ago.

The land we see today has been modified by erosion and glaciation. As the ice retreated, and especially with the last retreat about 12,000 years ago, large amounts of glacial moraine and till were left behind, of such quantity as to overspread the low-lying coastal tracts. New stretches of coastal plain were formed, leaving former cliff lines inland. You can see this in the coastal strip between Aberaeron and Llanrhystud, for example. In some places the glacial debris is of such depth that it has formed its own coastal cliffs, such as at Llansantffraid. At Wallog, moraine forms the remarkable bank of Sarn Gynfelyn, stretching way out to sea, a survivor of thousands of years of tides and storms. Further up the coast, under the sea, lies the similar bank of Sarn Badrig.

At some places, such as off the coast of Borth, evidence of former land lies in the remains of submerged peat banks and old tree stumps still in their original positions, visible at low tide.