Anyone who has ever pondered over an Ordnance Survey map of the Kent Downs area may well have come across the mysterious term 'denehole'. Scattered at seemingly random places on the map, you may well be forgiven for thinking that the word is at best a typographical error and at worse the cheeky antics of a cartographer determined to inject some intrigue and mystery into the map making process. Indeed, the mere mention of the word 'denehole' in certain circles has been known to conjure up images of secret caves guarded by knobbly kneed and snaggle toothed witches !! So what does this term mean and why do the Kent Downs seem to be the host of this strange feature ?!

A 'denehole' or 'danehole' is essentially an underground structure consisting of a number of small chalk caves entered by a vertical shaft. The chalk uplands of Kent once contained many hundreds, if not thousands, of deneholes of various types and the origins and purpose of these man made excavations have been the subject of intense interest and debate. In Victorian times many theories were put forward to explain why these structures were excavated, varying from Druids temples, flint mines and ancient hiding places to elaborate animal traps. However, the widely accepted view now is that these holes were in fact simple chalk mines. The vast majority were sunk to obtain an unpolluted supply of chalk to spread on the surrounding fields as a fertiliser. To modern eyes it is puzzling why a hole would be sunk sometimes to 20 or 30 ft deep when chalk might occur at the surface ! The simple answer to this is that the shallow chalk was probably not on the farmer's property since land tended to be owned in much smaller parcels then. There was also a belief that deeper chalk was regarded as being 'fatter' i.e it contained higher concentrations of elements such as magnesium.

With the improvements in agriculture over the last century, the use of the denehole, many of which date back to the 13th and 14th centuries, has long since disappeared, and most have been filled in or blocked up. Farmers do still however add chalk to their fields where necessary. Although no longer used, deneholes do still exist in woodland and hedgerows and can often provide a valuable habitat for wildlife such as bats and insects.

You must remember that most remaining deneholes are on private land and more importantly that caves are dangerous places. They should never be explored without the prior permission of the landowner or without guidance from a professional caving organisation.