|BGS Image ID: P805290|
Descending a Denehole at Hangman's Wood at West Thurrock, Essex. 1908. From the GA 'Carreck Archive'
'In the course of ploughing this field the horse's feet broke through the surface. We procured a rope and the pole of a waggon and investigated the interior. The shaft descended through about 12 feet of Thanet Sand and entered into a beehive-shaped chamber about 20 ft. high. These deneholes were formed in getting the chalk in past ages for marling the land.'
Deneholes are typically about 60 feet deep with steps cut into the side of the shaft to allow climbing in and out. At the bottom they open out to a domed chamber, often with sub-chambers.
It is though that chalk was mined this way from pre-Roman times.
Photographer: T.W. Reader