Stone Circles

Stone circles in Britain marked a move away from henges of circular banks and ditches. They were only widely surveyed for the first time by Alexander Thom and some of his surveys are provided here. Thom's geometrical ideas for these circles, whilst still contested, provide clear evidence of advanced horizon astronomy, "sacred" geometry and landscape geodesy often linking sites. Arguments as to whether ropes were used or whether alignments really existed prove fatuous unless based on efforts to understand such ancient skills without prejudice.

Alexander Thom Ll/l Class III Survey

Construction: Type A flattened circle the same shape and size as Burnmoor L1/6E. Diameter 107.] ft = 39.4 my. Perimeter 120.4 = 48.2 my. It is remarkable in that 4 astronomical lines came from the geometry of the layout. See survey. It is interesting that the circle at Bummoor (LI /6E) is almost the same size and shape. See second plan where they are superimposed.

Castle Rigg

Thom's Castle Rigg Plan
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Alexander Thom B7/1  Class II Survey

Construction: Three hollow cairns with rings. On the NE circle we have drawn an egg type I which is based on a 6, 8, 10 triangle. This has a peri­meter of 125.36 my = 50.1 mr. The middle circle has a diameter of 104. 8 ft that is 38.5 my, perimeter 121.0 my =48.4 mr. The south circle has a diameter 104.1 ft which is 38.2 my and perimeter is 120.1 my = 48.1 mr. The small circle of stones to the north west has a diameter of 13 ft which is 4.8 my giving a perimeter of 15.0 my = 6.0 mr. There are remains of another circle about 16 my diameter to the east of the middle ring.

Clava Cairns B7-1

Almost all of the different types of megalithic building [1] were evolved in the fifth millennium (5,000-4,000 BC), in the area around Carnac on southern Brittany's Atlantic coast. This includes the stone circles later extensively built in the British Isles.  When Alexander Thom surveyed these, between 1934 and 1978, he found them to be remarkably technical constructions, involving sophisticated geometrical ideas. It was only in the mid-seventies, when Thom came to Carnac, that the same geometries were found applied within Carnac's stone circles though at that time it was not known that Carnac's monuments preceded those of Britain by at least a thousand years.


[1] Megalithic building types include standing stones, stone circles, stone rows, dolmen, chambered and other cairns.

After an initial enthusiasm for Thom's work, in the late 1960s and early 1970s, British archaeologists chose, with very few exceptions, to refute the entire notion that the Neolithic could have been constructing such technical geometries which, as far as our History would have it, would only have become possible after the development (over two thousand miles away in the ancient near east) of a functional mathematics which culminated in Euclid's classical work on analytic geometry, Elements. Thom's use of geometry therefore seemed anachronistic to archaeologists and to accept it would have required a revolution in our thinking about the megalithic; for this there was little appetite. It was easier to falsify Thom's hypothesis with new work concluding that, for example, "stone circles were distorted so that the audience could see all the rites; and the principals could occupy visually focal positions facing the spectators.", clearly indicating the current "comfort zone" within archaeology in which unquestioned ideas about superstitious rites are used to supersede Thom's accurate and well founded proposals, of a megalithic technical capability, as being overly technical. The problem with inventing such ancient rites as being the primary purpose for stone circle construction is that, whilst refuting Thom's proposal, it definitely cannot be proved, cannot be disproved; Talk of rites as being the reason for stone circles is not delivering a scientific theory and Thom's proposals are not disproved by such ideas. 


Castle-Rigg Long-Meg

Figure Thom's site plans of two of Britain's finest surviving Flattened Circles, Castle Rigg (Type A) and Long Meg (Type B). Castle Rigg points (within a degree) to Long Meg, on a bearing which follows the diagonal of a two by one (east by north) rectangle, as if (despite some Lake District mountains in between) the two sites were related when built and hence contemporaneous.