The crumbling cliffs of Dover: Now France is even further away as thousands of tons of chalk crash into sea after frost and drought


For centuries the cliffs of Dover have stood watch over the Channel, a symbol of this country’s defiant spirit.

But their chalky whiteness is a clue that they are not as sturdy as we might imagine. In fact, they are steadily crumbling away, continually exposing fresh rock.

And every now and again there’s a major collapse like this one – when an area the size of a football pitch fell away, sending thousands of tons of rubble crashing 300ft down on to the shore.

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An aerial view of the latest chalk slip at the White Cliffs of Dover The collapse may have been caused by rain over the winter months being absorbed into the chalk and freezing The Kent landmark has suffered large rockfalls before, most significantly in January last year When the cliffs tumble, locals have described it as 'like a lorry going down the hill' A spokeswoman for the National Trust - which looks after parts of the chalk grassland in the area - said the cliff-fall happened between Langdon Cliffs and South Foreland Lighthouse

Collapse: Thousands of tons of the White Cliffs of Dover have plunged into the sea in a landfall last Friday, Dover Coastguard said

The fall on privately owned land near Crab Bay is one of the largest in living memory.

Erosion causes the cliffs, immortalised in song by Dame Vera Lynn, to retreat at a rate of about half an inch a year.

This huge fall has been blamed on February’s chilly weather.Rain has been absorbed by the chalk and has then expanded as it freezes.

Dover Coastguard said no one was injured but that it serves as a reminder that if people are walking along the cliff-top or underneath, that the cliff can crumble away

Cliff investigation: Dover Coastguard said a full survey has yet to be carried out to determine the exact amount and length of cliff that crumbled on Friday

Collapse: Thousands of tons of chalk fell from the white cliffs of Dover in an area known as Crab Bay. Here a woman surveys the damage

HOW THE CLIFFS WERE FORMED

On a clear day you can see right across from the Dover cliffs to the cliffs on the French coast at Cap Gris Nez, proof of the continuous strata of chalk. About 70million years ago this part of Britain was submerged by a shallow sea. The sea bottom was made of a white mud formed from the fragments of coccoliths - the skeletons of tiny algae which floated in the surface waters of the sea. This mud became the chalk. It is believed to have been deposited very slowly, probably only half a millimetre a year. In spite of this, up to 500 metres of chalk were deposited in places. The coccoliths are too small to be seen without a microscope but if you look carefully you can find fossils of some of the larger inhabitants of the chalk sea such as sponges, shells, ammonites and urchins.

(Source: Dover Museum)

This cracks the rock, eventually weakening it enough to cause a major collapse. The Dover Coastguard said: ‘It appears that it crumbled at high water so there was no one down below.

‘No one was injured but it does serve as a reminder that if people are walking along the cliff-top or underneath, that the cliff can crumble away.

'Over the years and around the country, including along the coast at Beachy Head in East Sussex, cliffs can fall after water expands when there has been freezing conditions. ’

There is a footpath at the top of the cliff just a few yards from what is now the edge.

When the cliffs tumble, locals have described it as 'like a lorry going down the hill'.

One local, Will Harding, 22, said: ‘I don’t think about the drop too much when I’m up there.

‘But when you see it like that it makes you wonder how safe it really is.’

Sam Wydymus, 40, co-owner of the nearby Coastguard pub, said the last major cliff fall in January last year – which was less severe than this one – had caused panic on the beach below.

He said: ‘That happened during the day and was quite scary, with people screaming on the beach. There isn’t any physical warning beforehand. When it happens, it just happens.’

A spokeswoman for the National Trust - which looks after parts of the chalk grassland in the area - said the cliff-fall happened between Langdon Cliffs and South Foreland Lighthouse.

She said: 'To alert walkers, the National Trust has sited several warning signs at several starting points of the walkways on to the cliffs.'

The cliffs stretch east and west of Dover for a total of eight miles.

Cliff face fall: The collapse may have been caused by rain freezing after being absorbed into the chalk and then expanding, causing it to weaken

Immortalised: A Spitfire flies over the White Cliffs which were popularised by Dame Vera Lynn's wartime song The White Cliffs of Dover

Famous landmark: The White Cliffs of Dover, with a lighthouse on top, seen from the car ferry port