Stackpole Head sea cave

Cliffs and sea cave at Stackpole Head, Pembrokeshire.

The shattered limestone at the top of the cliff is probably due in part to intense frost shattering during the last glacial period, the Devensian, when this part of Pembrokeshire was free of ice, but subject to severe cold and permafrost conditions. At that time the sea level would have been much lower - perhaps by as much as 100 metres - and the coast line would have been some way out beyond the present day cliff line.