Observatory at Ratcheugh Crag (Longhoughton) - 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The information on this website is based on a range of published and unpublished works.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) Ordnance Survey Map 1:10,000 1977
(2) List of Buildings of Special Architectural or Historic Interest DOE (HHR) Alnwick RD Northum May 1969, 32
(3) List of Buildings of Special Architectural or Historic Interest DOE (HHR) District of Alnwick: Longhoughton 01-Sep-1988 (109)
(4) 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/]