Penwith has a number of double menhirs, all of them within 20-100m each other, clearly erected as double menhirs – there is something intentional about this.
The Pipers - SW in the foreground, NE in the background
Double menhirs are all in the southern conglomeration of ancient sites – implying that this was a geomantic style the builders of the southern system considered important.
The southern sites certainly do have differences of style to the northern ones – these two sectors of Penwith were seemingly built and run by different people with marginally different ideas, and living in rather different landscapes, up to a day's walk from each other.
The fields and hedges of the relatively recent agricultural landscape have decontextualised these double menhirs, so that it is not easy nowadays to see how the ancients meant them to look, in terms of their visual surrounds and landscape context.
Polarity of purpose
In some cases most alignments coming in from elsewhere seem to go to one of the menhirs (such as at Redhouse and Chyenhal). In the case of the Pipers, part of the Merry Maidens complex, local alignments within the complex go to Pipers SW while alignments from the rest of Penwith go to Pipers NE.
Each of the two menhirs thus had a different purpose. Presumably this has something to do with polarity – up-down or in-out.
Some alignments seem to pass between these paired menhirs without hitting them exactly.
This is troublesome inasmuch as it confronts our normal accuracy rules, yet surely there must be some significance to it, since it happens in a number of cases.
On consideration, we have decided that these are valid alignments. Though they do not align exactly with either stone in a pair, passing between the stones must have some significance. Examples are found at Redhouse, Drift, Bunkers Hill and Boscawen Ros double menhirs.
The Drift menhirs
On the map, the orientation of these paired menhirs is marked in small green lines (zoom in to see them). These lines have no other significance than this. Azimuths of the lines are provided in the info-popups on the map. These alignments might be either astronomically or topographically based.
Whatever the purpose of these double menhirs, they are quite unique to the southern part of West Penwith, and their purpose remains enigmatic.
Carn Lês Boel
Carn Les Boel gateway stones - the one on the right is recumbent
At Carn Lês Boel there is a pair of menhirs, one of them a propped stone underpinned by some smaller stones that lift it slightly off the ground (see right), and the other fallen, embedded in the ground (to the right of the picture).
Together they constitute a double menhir, but probably of a different kind. They clearly acted as a gateway to the carn itself (and you definitely feel you’re crossing a threshold when you walk between them).
This gateway theme is also to be found at Faughan Round. But the other double menhirs mentioned above don't seem to serve a 'gateway' purpose.