English: Crumbling cliff base The cliff face here is wet because of water trickling down from the landward side. Wave action is undermining the cliff face from the seaward side; here the sea is eating away at the layer of dark clay which forms the cliff base - crumbling and eventually toppling onto the beach. The layers above are slipping downwards, taking all vegetation with them. The exposed cliff face is easy prey for wind and weather. As can be seen at left, all that remains of the revetments along this section of coastline is a skeleton of bare posts with nothing much in between. Coastal erosion in the vicinity has been estimated at an approximate rate of one metre/year, which accounts for the loss of a strip of land approximately two kilometres wide since the Roman invasion in 43 CE, resulting in the disappearance into the sea of several medieval villages.