If you happen to be passing Lyme Regis in Dorset, pop into The Fossil Shop for a journey back in time. From behind a replica shark jaw – replete with real, 250-million-year-old Florida shark teeth – emerges a shopkeeper. ‘All right?’ he asks cordially, and proceeds to explain how the fossils are created.

‘The word ammonite comes from the Greek for ram’s horn,’ he begins, as I warm to the theme. ‘The shell is like a diver’s buoyancy jacket, but when the animals die, they lie on their side.’ He demonstrates with a plastic sea creature, its tail curled into a spiral.

As the layers of sediment gradually cover it, the weight crushes the soft shell, leaving a perfect specimen. He briefly digresses into stupid tourists being rescued from the coast, up to their necks in mudslides. ‘Idiots,’ I nod knowledgably, glad that I’d washed off the mud and changed my jeans.

Fearsome Predator

On the wall, a newspaper clipping tells of a recent find here: a 60ft long pliosaur, with a bite four times more powerful than a T-Rex. It is the biggest-ever sea killer found on a UK beach.

‘They reckon there’s a hole in the seabed down at Portland Bill,’ continues my newfound friend in The Fossil Shop. ‘It’s probably full of ammonites, but it’s too dangerous to get them out.’ Well, I think I’ll head down there then, for a look. ‘Have a crab sandwich for me,’ he chirrups.

En-route I have cause for an emergency stop. Sarah, a 22-year-old photographer, is sitting on the road at a bus stop, looking a little forlorn. Her feet hurt, which is hardly surprising as she walked 29 miles of the South West Coast Path yesterday. I don’t really like to mention the paltry seven I managed, but then I seriously doubt whether she almost vanished into quicksand. Anyway, without applying the handbrake, I open the passenger door and leer with wanton perversion. ‘Need a lift?’

Another Fearsome Predator

Cor, her feet must really be sore, because she tosses her rucksack into the rear seat and climbs in next to me. Are girls supposed to accept rides from strangers nowadays? Well, as it turns out, Sarah is the perfect girl to buy lunch – she doesn’t want any. (No doubt my father would say she needs slapping as a result.) Nibbling on a meagre flapjack, she gazes out to sea while I cram in a rather good crab sandwich, savouring each delectable morsel.

Exploring the rocks by the lighthouse, it feels like the end of the earth here – the calm before the storm, if you like. Well, the storm soon comes. Half an hour later, the car runs out of water and grinds to a halt in Asda, Weymouth.

‘It’s the only Asda in Dorset,’ says a supermarket shelf-stacker when I ask for an address to give the AA. Well, let’s hope those directions are enough, then. Oh, and I never did find that swirling vortex at Portland Bill. I shall have to come back to this gorgeous part of Britain another time..

[Photos courtesy of Lawrie Cate and myDefinition]