Clwyd Cap on Halkyn Mountain
Introduction
The photograph on this page of Clwyd Cap on Halkyn Mountain by Aaron Thomas as part of the Geograph project.
The Geograph project started in 2005 with the aim of publishing, organising and preserving representative images for every square kilometre of Great Britain, Ireland and the Isle of Man.
There are currently over 7.5m images from over 14,400 individuals and you can help contribute to the project by visiting https://www.geograph.org.uk

Image: © Aaron Thomas Taken: 5 Nov 2006
The metal structure is known as a "Clwyd Cap", and was used to cap open mineshafts. This former lead mine would have been created in the 19th or early 20th century. Many Clwyd Caps are also covered in rocks and cement to completely seal the mineshaft.