Groove in hillside
Introduction
The photograph on this page of Groove in hillside by Trevor Littlewood 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: © Trevor Littlewood Taken: 11 Oct 2019
The groove is most likely one created by a stream but OS mapping does indicate mining in the vicinity, so that's a possibility too. The mountain beyond is Mynydd Mawr.
