From The Downs at Herne Bay, I headed for sea level and Reculver in that order. The coastal protection schemes in place here, and the graded cliffs, have resulted in a very popular dog-walking area but, given its proximity to such a large urban area, it is none the worse for that. It could be argued that this man-made intervention has actually enhanced the cliffs, providing stability and an environment for wild plants to flourish (a particularly fine pepper saxifrage among the vetches and grasses) and attract birds, butterflies and bees.

About a mile further east most of the trappings of civilisation have gone. This is real SSSI land, complete with gooey mud and dangerous cliffs. It’s wise to set out on a falling tide.

Bishopstone Glen brings the first taste of the ‘real’ North Kent cliffs. Below the thin top layer of London Clay, the Oldhaven Beds (recently redefined the Herne Bay Member) are separated from the Woolwich and Reaching Formation by a dramatic line of black flint pebbles - well-rounded, they suggest a fluvial deposit. It’s the first of the sand martin colonies which fill every twist of the cliffs sheltered from the coldest of the north winds. In mid-August the hundred-plus pairs were still busy feeding their broods under the unblinking eyes of more than one kestrel. Closer inspection of the cliffs reveals myriad tiny holes, home to mining bees and rare digger wasps.

Between the Glen and Reculver, the geology of the area is plainly visible, thanks to a bold initiative by the City Council, with advice from the Nature Conservancy Council. Rather than smother the base of the cliffs with concrete to halt erosion, a kind of damage limitation exercise is in process. At strategic points on the beach granite boulders imported from Scandinavia slow the natural erosion to an acceptable level. Tiny corries and gravity-defying grottoes testify to the regular small landslips, but this is what ensures that the cliffs remain vertical and reveal the different strata of sand and clay, the lower Thanet Formation ribboned with paper-thin fossilised bivalve shells from 60 million years ago. When landslips do occur, the debris (the talus) is removed, to prevent the gradual formation of the type of graduated cliff found further west.

This is bouncing bomb terrain, largely unpeopled, and in parts unchanged from the Barnes Wallis years. The shoreline here may not be renowned for the richness of its bird life but at the right time of the year it is possible to see a great deal: curlew, whimbrel, godwit, oyster catcher, sandpiper, turnstone, Brent geese, tern, ringed and golden plover, sanderling, dunlin, fulmar, divers and duck. At anything but high water, the rocky shoreline is a treasure chest. Look for fossil sharks teeth and bring your I Spy On the Beach book.

And then, as suddenly as it started, the wild area ends. The twin towers of St Mary’s ruin are ahead, protected now by a seriously large chunk of Norway. Upwards, off the beach and across to the visitor’s centre. The centre is manned by enthusiastic and knowledgeable volunteers but it’s closed on Mondays during the summer and many other days as winter draws on. I was drawn to a simple map on one display, showing the extent of the Wantusm channel in Roman times. Fascinating. The whole of today’s caravan area would have been under water. Hmmm… now there’s food for thought. And by the way, the pub usually does an excellent line in Something Tasty With Chips.

And so to higher ground. Keeping a respectful distance from the edge of the cliff, the ‘high road’ back gives a wonderful view on a clear day, across the estuary and up the North Sea as far as the River Crouch. Gulls, crows and the occasional kestrel cruise the thermals along the cliff. Effortlessly, they glide past at waist height, seeming to mock the ungainly human mode of locomotion. The meadow on the clifftop here is cut in late July, after the wild flowers have set their seed and the ground nesting birds have fledged their young. Watch out for warblers, pipits, wheatear, wagtails, tits and wrens. Keeping as close as possible to the sea, it’s possible to join the Bishopstone Glen Trail and, for half a mile or so, enjoy the contrast of a wooded trail before rejoining civilistion by easy stages at Beltinge. The Glen itself harbours much of general and specific interest in the tiny, ancient river gorge..