Kimmeridge and Ghostly Tyneham

There's a bleakness about Kimmeridge Bay which the high energy of the surfers and the cheerful picture of families on the beach, eyes down as they potter in the rock pools, can't quite dispel. Giant slabs of black rock shelving out to sea, with crumbling cliffs topped by clumps of wild cabbage, create something of this mood. The slow, steady nodding donkey-head of the oil well above a little terrace of unmistakably industrial cottages reinforces it.

The story of the bay is intriguing. Iron-Age tribes spotted the potential of the band of bituminous shale that runs through Kimmeridge, polishing it up into blackstone arm rings and ornaments, and later into chair and table legs. People have have been trying to exploit it ever since. The shale, permeated with crude oil, is also known as Kimmeridge coal, but successive attempts to work it on an industrial scale seemed doomed to failure. These included alum extraction (for dyeing) in the 16th century; use of the coal to fuel a glassworks in the 17th century (it was smelly and inefficient); and use for a variety of chemical distillations, including paraffin wax and varnish, in the 19th century. And for one brief period the street lights of Paris were lit by gas extracted from the shale oil. However, nothing lasted very long. Since 1959 BP has drilled down 1,716ft (520m) below the sea, and its beam engine sucks out some 80 barrels (2,800 gallons/12,720 litres) of crude oil a day. Transported to the Wytch Farm collection point (near Corfe Castle), the oil is then pumped to Hamble, to be shipped around the world.

In contrast to Kimmeridge, just over the hill lies Tyneham, a cosy farming village clustered around its church in a glorious valley. As you get up close, however, you realise that it's uncannily neat, like a film set from the 1940s - Greer Garson's Mrs Miniver could appear at any moment. There's a spreading oak tree by the church gate; a quaint old phone box; even a village pump. The gravestones all look freshly scrubbed - no lichen here. The farmyard is swept clean and empty. The stone cottages are newly repointed, but roofless. And the church, as you enter on a chill mid-winter day, is warm! Inside is an exhibition to explain all. The villagers were asked to give up their homes in December 1943 for the 'war effort', and Tyneham became absorbed into the vast Lulworth Ranges, as part of the live firing range. It's a touching memorial, though perhaps nothing can make up for the fact that the villagers were never allowed back to their homes. Emerging again, you half expect to see soldiers popping out of the windows, but relax, you can only visit when the ranges are closed.

While you're there

The Clavell family have been at Smedmore since the 13th century. In 1575 John Clavell was attempting to exploit the Kimmeridge shale for alum (an essential ingredient for the dyeing industry), and the current Smedmore House, a handsome twin-bayed affair dating from 1761, still keeps a firm eye on activities in the bay. The house is open in high summer when you can enjoy its attractive gardens, the rococo details, period furniture and a museum collection of dolls.

What to look for

Kimmeridge's unique combination of clear, shallow water, double low tides and accessible rocky ledges make it the ideal choice for a pioneering underwater nature reserve. The double low tide is at its best in the afternoons - effectively, the water may stay low all afternoon, allowing optimum access to the fingers of rock which stretch out into the bay. The low water uncovers a world of rockpools and gullies alive with seaweeds, anemones and creatures that include crabs, blennies and the bizarre pipe-fish. Learn more at the Fine Foundation Marine Centre.

Where to eat and drink

The post office and store in Kimmeridge, just below the church, also doubles as a café. A favourite hang-out for surfers, it's open all day for meals and snacks, coffee, tea and drinks, and locally produced Purbeck ice cream. There's a small seating area outside and a good-sized car park.