As I have now discovered and deciphered, the nearby and somewhat higher elevated Carn Menyn, formerly and more correctly Carn Meini, given by the Ordnance Survey as Carnmenyn, represents the "main" (=Meine) Carn in the astronomical system in Pembrokeshire, Wales, which marks a hermetic planisphere of the heavens at that localization ("as above, so below").
Go to Landscape-Perception.com to see a more detailed map of Carn Menyn.