About the Making of the Maps
Researching alignments is not as easy as it might appear, though occasionally an alignment pops out easily on a hunch.
Sometimes one is spotted but then it proves to be inaccurate, after all possible fits and permutations have been tried. It is important to avoid forcing, fiddling or falsifying alignments since sooner or later they will prove problematic, and they are open for checking by anyone.
There are complexities too: a site’s position might not be clear, either on the ground or in aerial photos, or slightly differing map references might be given by different sources, or the nature of the site might be unclear or disputed – in each of these cases careful judgement must be applied.
The maps of Cornwall were made using the satellite photography of Google Maps – this is much more useful for examining the precise location of sites than customary printed Ordnance Survey maps, where the map-symbols used can actually stretch 30-50 metres across the ground. Satellite maps can be more accurate for our purposes.
The first task was to populate the base map with prehistoric sites – a lengthy task taking a few years, using sources ranging from Heritage Gateway, Pastscape and the Megalithic Portal to Meyn Mamvro, books and personal communications. A digital base working map showing all known sites in Cornwall was eventually created – arranged in seven layers, each with its own database from which the map is drawn when it is called up on-screen.
Then alignments were researched and added to the map – themselves in three layers. The layered data was then transferred into a range of publicly-available maps highlighting certain areas (such as Scilly or the Lizard) or certain factors (such as ancient sites or backbone alignments) or matters of interest (such as near-parallel alignments or radial alignments around Carn Brea).
In compiling ancient site alignments on the maps a three-metre (9ft) accuracy rule was observed, with an occasional five-metre (15ft) leeway for big sites. This is a tight accuracy standard. In cases where an alignment passes close to an important site, say 10-50 metres (30-150ft) away, without touching or tangenting it exactly enough, the site is noted in parentheses in the alignment listings though it is not itself counted as an alignment-determining site. Existing alignments found by earlier researchers (particularly John Michell) and catalogued by Raymond Cox of Meyn Mamvro were checked and entered on the map. In doing so, further alignments were discovered.
One evening early in 2015, on a hunch, a new type of alignment, the backbones, was unearthed. This was rather a eureka moment. I was contemplating St Michael’s Mount and Cape Cornwall, two similarly-shaped cliff sanctuaries, only to find that a straight line I drew between them went right through the platform barrows on Botrea Hill, just above my house. This started bells ringing.
I had spent a lot of time at the barrows and, while they command a remarkable panorama, they had not appeared to be a really major site – visually, the are not impressive, and the sit on a furzy moor that few people visit. But here they were, at the highest point of an alignment between these two very significant sites. Later, the barrows proved to be a major node involving more such alignments: they sit at the crossing point of alignments passing, astonishingly, between three pairs of cliff sanctuaries – St Michael’s Mount and Cape Cornwall, Pendeen Watch and Kemyel Point, and Gurnard’s Head and Tol Pedn Penwith.
Seeking further alignments radiating from St Michael’s Mount, I quickly found several: the Mount, Lanyon Quoit and Pendeen Watch were aligned, as were the Mount, Boscawen-ûn and Maen Castle, or the Mount, the Merry Maidens and Treryn Dinas. It all snowballed from there, with findings duly checked by Cheryl Straffon and Raymond Cox, catalogued by Ray, made available on the Ancient Penwith and Meyn Mamvro websites and ongoingly updated ever since.
Arguably, backbone and long-distance alignments can be permitted a little more inexactness than local, shorter alignments, by dint of their length and magnitude – the magnitude being judged by the importance of the sites they connect. Even so, most backbone alignments on the maps are surprisingly exact, though in few cases alignments pass close to sites without exactly touching them.
To give an example, at Boscawen-ûn, one backbone alignment passes just 20 metres (60ft) from the circle – yet it is 95km long, stretching from Carn Lȇs Boel to Stannon Circle on Bodmin Moor. Yes, the alignment is technically inaccurate at Boscawen-ûn but, at that distance, despite the inaccuracy, it is significant that the alignment comes that close to the stone circle. Actually, it hits a nearby, now-removed boulder cairn called the Money Rock, close to Boscawen-ûn and part of its complex – so the Money Rock acted as a proxy for the stone circle. This is quite common with stone circles and other key sites – they can have outlier menhirs or cairns that act as proxies or relays. Some alignments exactly strike the main site and some go to a proxy. Two examples of proxies are The Pipers at the Merry Maidens and Boswens menhir near Tregeseal.
Just because many barrows look similar, this does not mean all barrows are the same. For some barrows, no alignments can be found. Some lie on one detectable alignment while others are at intersections of multiple alignments, suggesting that these serve a distinct geomantic purpose as focal or nodal sites. Many burial barrows and cairns lie on no alignments at all. Each barrow thus has a unique character.
The same applies to menhirs and other sites, which are also variable in geomantic purpose, and this purpose can be seen by examining other sites that they are aligned with and by looking at other locational factors. A site’s role in the whole system is defined by the site itself (its look, feel and location), and by its relationships with other sites (intervisibility, alignments and energy-lines).
The maps are regularly reviewed and updated as new information comes in or as new ideas are tested. The mapping process started with West Penwith in 2014-5, then Scilly in 2016, then East Penwith, Kerrier/Carrick in 2019 and East Cornwall in 2021. The most accurate and up-to-date versions are the online Google maps. JPG image maps are drawn from these, but these are updated once every two years or so only. They do not contain the same reference information that is built into the Google maps of Cornwall.