Coal Working (Heddon-on-the-Wall) - Source of Reference
The information on this website is based on a range of published and unpublished works. Below is a list of the source of information used in writing this record.
1) OS 6" 1st Edition 1865
2) This record includes National Record of the Historic Environment Information provided by Historic England on 4 January 2021 licensed under the Open Government Licence [http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/]
2a) Vertical aerial photograph reference number RAF/58/2685/F22 157 23-JAN-1959
3) OS Maps API (WMTS), accessed 07-DEC-2021