Photo ©  Roger Langereis

The White Cliffs, up to 300 feet high, are made up of millions of small sea creatures and coral from the bottom of a long ago tropical ocean - the chalk is porous, soft and easily worn by the action of the waves, and the whiteness of the cliffs is pure lime, manufactured by living things.

In the cliff-face you can see the lines of black flint which is made from a very hard mineral, silica - sea creatures such as sponges had skeletons of silica rather than lime. The silica from these creatures remains dissolved and deposited as flint nodules in the chalk and most of the pebbles at the foot of the cliffs are flint, and the rocks speckled by it too.

Kittiwake, fulmars and peregrine falcons all make their home on the white cliffs which are eroding at 2 - 5 cm a year on average, although a section can lose a metre or more in a sudden cliff fall. The Gateway to the Cliffs Visitor Centre features a range of displays and computer interactives telling the story of the White Cliffs from pre-history to the present day.

Information National Trust