The Jurassic Coast

One summer I decided to walk along the Dorset coast from Swanage to Weymouth. Not far on the map, until you take a good look at the contours. The distance must be almost as much up and down as it is along. I deliberately travelled light, but not light enough. By the time I got to Weymouth I was ready to head for the nearest garage for a new pair of knees.

But I’m getting ahead of myself. I haven’t even left yet, and in any case, the Dorset coast is a very special place about which I need to say a something more before I set off. This stretch of England’s southern coastline is part of a World Heritage Site known as the Jurassic Coast. In fact it is also partly Cretaceous, and beyond Weymouth, partly Triassic too. That is to say, its folded, slipped, crushed, multi-layered and undulating cliffs boldly display some 185 million years of geological history. The rocks on show include Portland Stone, a limestone used in the construction of superior buildings; Purbeck Marble, which is not actually marble, but polishes well, so will do; and Kimmeridge Clay, which is not clay as we know it, having been geologically pressured into becoming stone.

In places the cliffs are also dripping with fossils – ammonites and belemnites (‘Devil’s fingers’) especially , and sometimes more or less complete skeletons of ichthyosaurs and plesiosaurs – marine dinosaurs. This coast is also quite stunning as you try and imagine how these layers of planet earth could possibly have been so convulsed, or as you gaze down from the height of the cliffs to the grey – occasionally blue – sea below, and away to the horizon.

Clearly, if you haven’t been there, you need to go.

The Jurassic Coast officially begins on the Isle of Purbeck – which isn’t an island, its a peninsular. More precisely it begins at Old Harry and his (latest) Wife, who are, respectively, a chalk stack and a chalk stump, surrounded by sea. They stand a couple of miles north-east of Swanage, off Handfast Point. (Harry’s previous wife collapsed in 1896, while the new one was apparently formed by another collapse of the Point). I began my walk, however, by climbing south out of Swanage until I came to the slope above the Anvil Point Lighthouse. I sat and ate my picnic lunch and watched a flight of black and ragged ravens cavort along the edge of the cliff and around the lighthouse below. Then I set off, as all good adventures do, westwards, along the cliff path.

My first objective was to reach Dancing Ledge. This is a wide area of rock at the foot of the cliff which gets its name from the notion that at certain stages of the tide the ledge appears to dance as the sea bobs over its undulating surface. However, what I was after was the rock-cut swimming pool that was blasted and cut into the ledge at the beginning of the twentieth century for the use of the local schools in and around the nearby village of Langton Matravers (Dorset is particularly wonderful for its place names). There were a number of people there when I arrived, but not many swimming. The tide was just up to the ledge and washing into the pool; the sun was partly obscured by cloud. But I had come to swim and it was warm enough. I swam. The pool was neither deep nor large, and I was sharing it with a dad and his son, but there was room enough. I managed a few short lengths; I sat submerged to my moustache and watched the tiny waves come washing in.

There was nothing between me and the endless ocean . . .

However, I couldn’t stay all day.  I had a coast to walk.  I dressed and left.

Next stop was St. Aldhelm’s Head, partly because I needed a sit-down by then, but otherwise because I came upon an ancient, stone building on the very top of the headland. It was clearly a chapel, as a stone cross sat on the apex if the roof. But it was square. It measured perhaps ten yards on each side and was surrounded by a low, circular earth bank. I entered through a round-arched, very obviously Norman, doorway on the north side, away from the wind. Inside, a squat, central pillar supported four ribbed vaults dividing the chapel into quarters. A most curious manner of construction for a chapel, Norman or otherwise. (In fact it may have originally been built as a watch-post and only later converted to a chapel). However odd, it was a comforting space to sit a while, enclosed by ancient stones – and also in the company of a new one. An altar of recently cut stone stood in one of the quarters.  It was installed in 2005 to celebrate the 1300th anniversary of the consecration of St. Aldhelm as a Bishop and was consecrated by the then Archbishop of Canterbury.

A long stretch of history by human standards, but built on and of an even longer stretch of geological time.

By the way, St Aldhelm’s Head and chapel are located in the parish of Worth Matravers. Matravers originates from the name of Lord Mautravers, and ultimately originates from the French “mal traverse”. This might be thought peculiarly appropriate by an unsuspecting walker struggling up and down the cliff-top path.

Me, for example.

I bivouacked that night at Chapman’s Pool, a sheltered cove a little further along the coast. The beds of rock which form the cliffs here are fairly level. The lower part is mostly landslip, above which rises the soft, grey rock which forms the majority of the cliff – Kimmeridge Clay. But then the clay is capped with a band of hard Portland Stone, the change from one bed to the other being quite abrupt. The rocks at Stair Hole, immediately beyond Lulworth Cove, which I reached the next day, were rather different. They are also made of Portland Stone, but in a series of narrow bands stood on end, bent and buckled over, and then back off up again, skyward. Of course they would have been horizontal once, when first deposited on the bed of a shallow sea, but great forces have clearly been at work. Stair Hole is a favourite destination for geology field trips, and together with the Cove, one of the most touristed parts of the Jurassic Coast.

I did not linger.

I set off instead for Durdle Door. Like Stair Hole, Durdle Door is a rock arch created by the pounding of the sea through a wall of limestone. It lies about a mile west of Lulworth. If you take the coast path you cannot miss it. Hoards of people were walking up the steps and over the rise of the cliff from Lulworth to visit Durdle Door. I planned to visit too. I walked with the hoards.

I missed it.

I saw it from the cliff path. I saw that there were lots of people there down in the cove. But I failed to register that it was Durdle Door. I just kept walking. Partly, perhaps, it was the hoards, from which I wished to escape. Mostly, I suspect, it was the can of lager I’d had with my picnic lunch on the top of the rise out of Lulworth . . .

[1]

At the end of the second day I came to White Nothe.

Here’s what you need to know about White Nothe:

‘It is the most westerly coastal exposure of the higher Middle and Upper Cenomanian Zig Zag Chalk Formation of the Grey Chalk Subgroup, before it condenses into the higher Basement Beds of south-east Devon. The Zig Zag Chalk Formation has a glauconitic, sandy base which rests, not on marly chalk typical of the main basin to the east, but on highly condensed Cenomanian Basement Beds. In turn, these thin Cenomanian deposits rest on a complex succession of Albian Greensand and Chert Beds. The succession at White Nothe has been described as the best demonstration of Cenomanian onlap in southern England.'[2]

Or, you might prefer to know that White Nothe is an enormous chalk headland, some 610 feet high. The name means White Nose. Someone was presumably suffering a heavy cold at the time of naming. The chalk cliff then extends and slopes gently down for a mile or so to the west. Beneath White Nothe and along the whole length of the mile lies The Undercliff. This is an enormous area of prehistoric landslip. It is a tumbled landscape of mini hills and dips, steep slopes and brief levels, all covered by dense tangles of hawthorn, blackthorn, holly and bramble, or thick tussocks of grass. The eastern end is remote and inaccessible, although there is apparently an old smugglers’ route known as the zig-zag path which runs down from the top of headland to the shore. The western end can be reached by a track and path or from the beach. This western end is known as Burning Cliff. An underground fire smouldered there from 1825 to 1827, fed by the bituminous shale which accompanies the chalk.

I stood on the top of the cliff at White Nothe and looked down on the Undercliff. There was no sign of a descending path. Anyway, the cliff was precipitous. But the Undercliff was irresistible. I found a slightly less precipitous edge – and went for it. I slipped and slid, but mostly I found that the force of gravity was more than made up for by the opposing impenetrability of the vegetation. My hat was snatched from my head. The blackthorn and brambles clung to me, forcing me to stop and extricate myself from their clutches. I lost the mug clipped to my rucksack somewhere on the descent. Nonetheless, I reached the Undercliff at last and turned to look back at the great wall of chalk above.

There was a peregrine hanging on the wind. He hardly beat his wings. He hung just above the cliff edge. He moved to the left sometimes, or to the right, surveying the expanse of the Undercliff below.

Suddenly a lone goose came in from the right, straight and level at half cliff height. The peregrine moved at once. Not a stoop though, more a matter of indignation at this outrageous intrusion into its airspace. It chased, not attacked – but the goose was on a mission and just kept going, and was soon gone. The peregrine returned to its patrol.

The next morning I positioned myself in front of Burning Cliff, just above the beach. The peregrine was there again, somewhat westward of where I had watched it the evening before. I soon saw that it was patrolling the entire length of the Undercliff. After a few minutes at the western end it would then drift to the eastern end for a while, and then return. And when the hunter had moved away the local wood pigeons suddenly appeared from the hawthorn trees in which they had been hiding. They dashed from one group of trees to another while they had the chance. I watched for an hour or so but I never saw the peregrine attempt a kill.

I have not mentioned that during the course of my pilgrimage along the Jurassic Coast there was a lot of rain. This is normal of course. But there was also sunshine, and clouds passing more or less grey and heavy, or white and billowing. Changeable is the word. And as the weather changed, so did the colours of the sea – and of the cliffs, with their layers of rocks becoming still more distinct when the sun was on them, and changing hue as the sun sank westward.

The drama of the Jurassic coast is not only in its rocks.

I was not the first to notice this. John Constable spent his honeymoon just beyond White Nothe at Osmington in the year 1816. He painted a number of views of Osmington Bay, and of Weymouth Bay beyond – the shore, the sea, the cliffs and the sky. In the most dramatic of these, the sky – which occupies three quarters of the canvas – rises like a vast tsunami about to crash down upon the tiny figures on the sunlit beach below. My favourite, though, is a view of the beach towards a low, grass-covered hill. Above it the clouds rise like billows of smoke, turning the modest English hill into an apparent volcano.

I have also failed to mention that all along the cliffs, from Swanage to White Nothe and on to Weymouth, there were Wheatears (Oenanthe oenanthe) .  I particularly enjoy the striking black mask of the male, and the way they perch boldly on fence-post or bush. It is a bird I tend to see only in high summer. This, it seems, is because I live in Hampshire, in the south of England. A few wheatears breed in the South, including in Hampshire, but far more breed in the north and the west of the British Isles. Most though breed further North still. In fact they breed nearly all round the north of the planet, from Alaska to Northern Asia. Having done so, however, they all, every one, then spend the winter in sub-Saharan Africa. Alaskan and western Canada breeders actually cross the entire continent of Asia to get to Africa. Birds from eastern Canada are believed to return by way of Iceland, Ireland, Portugal and the Azores. Some head south via Britain. This means that the wheatears I saw on the Dorset coast in August might have been British-breeding birds, but may well have come down from the arctic. In any case, one bird I disturbed on the coast path headed straight out to sea. I followed it with my binoculars until I could see it no more, still heading south. I felt peculiarly guilty. Had I scared it off before it was fully refuelled and ready to go ? Would it make it to its distant wintering grounds or would it falter and fail?

Fortunately, I will never know.

‘Wheatear’, by the way, is probably a smartening-up of the original ‘White-arse’, the bird’s white rump and tail being its most distinctive feature as it flies away from you.

I strolled in to Weymouth on the morning of the fourth day. I could have strolled in by the afternoon before, but I took one look at the grey and crowded town spread out below me and turned back up the path a way. I was not yet ready to end my itinerant and outdoor adventure. I bivouacked in the lee of a cliff-top hedge. Unfortunately I was accompanied by some hundreds of assorted tents. It was a camp site. I boiled myself some instant noodles and went to sleep.

I walked down into the town the next morning, along the promenade, and made for the railway station. There was no train for some time. This was a stroke of luck because it meant I could then stroll over the road and across a municipal car park and arrive at Radipole Lake bird reserve. The lake is completely surrounded by the town and its suburbs, and yet it hosts such uncommonly seen creatures in its reed beds as bearded tits, otters and bitterns.

I saw none of them.

However, I sat for some time and watched a multitude of sand martins busy over the water in low sweeps, quick climbs and instant turns – like miniature fighter planes, except that they are so obviously inoffensive and delightful.  An artificial ‘cliff’ had been provided to attract them, but breeding seemed to be over by now, so that they could devote themselves full time to flying.

Then I went back to the station and caught my train home.

*

[1] Saffron Blaze, via http://www.mackenzie.co – digitally altered.

[2] Geological Conservation Review Volume 23: British Upper Cretaceous Stratigraphy, Chapter 3: Southern Province, England.  Site: WHITE NOTHE (GCR ID: 208). http://www.jncc.gov.uk/page-2731. © JNCC 1980–2007.  Note that the reference is very nearly as incomprehensible as the quote.

 

 

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