The Neolithic and Bronze Age periods saw the use of large quantities of stone for building the chambered tombs and the settings of standing stones. Often large blocks of stone were used for the chambers of the tombs and the standing stones. In many cases some of these stones are tens of tonnes in weight.

The work of the megalithic builders is still much in evidence in the North and much has been written of their constructions which are well documented. What has been given less attention, however, is the possible source of their building material. Whilst some of the smaller stones may have been collected from the surface, undoubtedly some, in particular the larger ones, must have been quarried albeit often from surface outcrops of rock.

One site which has been identified in Orkney (Laing 1974 p.89) is on the slopes of Vestra Fiold, HY238215, which is considered to be a source of stone for chambered tombs or standing stones. Here the natural rock surface outcrops along the side of a hill. Being sandstone it splits easily along the bedding planes and along the length of the outcrop are to be seen a number of large slabs which have been removed. In some cases these large blocks of stone have been chocked up on smaller stones lying beneath them, thus giving the appearance of being ready for transportation perhaps on rollers.

In Caithness there are no such sites recorded. The writer has, however, noticed two possible sites which bear similarities to those at Vestra Fiold.

Near the summit of Cnoc na Maranaich, ND131331, along Dunbeath Strath, are the remains of a chambered tomb (Henshall 1963 p.269) with, close by, a large standing stone 2.5m high. Within the remains of the tomb are a number of large slabs of local sandstone, and 75m SSE of it a large capping stone still covers a burial cist. Running down the gentle slope of the hill in a south easterly direction is a natural outcrop of rock from which a number of moderately sized slabs have been removed and lie nearby in the heather. One slab is still supported on smaller stones giving the appearance of having been so positioned by human agency. Comparing this site with that at Vestra Fiold one is lead to the conclusion that it may have been the source of stone for the chambered tomb and the standing stone nearer the summit.

Another site in Caithness which has striking similarities to the previous two is at Upper Dounreay, ND008660. The area between here and the summit of Cnoc Freiceadain to the SE is rich in megalithic remains which include chambered tombs, stone rows and standing stones. A large quantity of stone was required for their building and may have been transported from a number of different sites but the one exhibiting the appearance of a possible source of material is that at Upper Dounreay. Here again the rock surface naturally outcrops in the side of a small hill on the top of which is a short horned chambered tomb (Henshall 1963 P.298). Some slabs have been removed from the outcrop where they still lie in a inclined position.

Other sites undoubtedly exist in Caithness and remain yet to be identified. Some, of course, may now be covered by the growth of vegetation which has accumulated over the last four thousand years or so. What would also be of interest would be to discover whether, for example, the Achavannich standing stones are of material native to that area or if they have been transported from another part of the County. Certainly there are other large slabs towards Stemster Hill which lie flat on the ground and give the appearance of having been transported part-way to the site.