This is an iconic place bringing back sweet memory to all of US who took the ferries to come to England. For almost 1,000 years, Dover Castle, perched on top of the white cliffs, has stared back at those who may have cast an envious eye at England from only 20 miles away.
But why are the cliffs so white? Well they are made up of billions of the crushed shells of tiny sea creatures. A hundred and fifty million years ago in the Cretaceous period, these organisms gradually settled in shallow seas.The sediments built up were gradually lifted to form the chalk cliffs.
These are eroded by the sea, keeping them white.
But where the sea cannot reach the cliffs because of beach and sea defences, then erosion stops and the cliffs become vegetated with trees and shrubs.
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