Description
The monument consists of a substantial earthwork which may be of any date between the Neolithic and Medieval periods, together with adjacent remains. The earthwork runs from the shore of the Loch of Stenness to near the modern shoreline of the Loch of Harray. Its line is approximately, but not exactly, that of the modern parish boundary between Stenness and Sandwick.
The earthwork is on average about 7m across and varies in height above the surrounding ground, reaching a maximum height of about 1.3m. Some of the variation in height may be original, rather than due to wear and tear. It measures about 415m in length W of the public road. It is sinuous, and its changes in angle do not seem to be directly related to topography.
The stone strainers of the fence preceding the present one survive, and there are lines of piled stones which undoubtedly represent attempts to stop up a gap at the bottom of the fence with stone strainers. It is the line of the former fence, associated with these features, which is shown on the current (May 1966) Ordnance Survey 1:2500 scale map, not the line of the present fence. There appears to be a well-built wall base, at least in places, which runs along a slightly different line to that of the earthwork.
There is a ditch or stream course to the N of the earthwork. Whether this is of the same original date as the earthwork is not clear. There are two large gaps in the earthwork which may be original, at about 105m and 220m W of the public road (measuring along the crest of the earthwork). A narrower gap, 4m across, occurs at a point 350m W of the road, at a point about 65m from the W end of the earthwork.
The area to be scheduled includes the earthwork and possible stone wall base, and areas to either side of the earthwork in which evidence relating to its construction and use are likely to survive. The area falls into two parts, shown in red on the accompanying map extract. W of the road it is a sinuous strip 30m wide and approximately 415m long, running between the shore of the Loch of Stenness and the W side of the road.
E of the road it is 20m wide and measures 42m along its N boundary and 18m along its S boundary: the N boundary coincides with a property boundary shown on the Ordnance Survey map. The scheduling is to exclude all the above-ground parts of all modern fences in the area
Statement of National Importance
The monument is of national importance as a major land division of potentially great age which divides off the Brodgar isthmus, including the Ring of Brodgar, from the north.
It may be a Neolithic or Bronze Age ritual boundary, or a Norse or medieval land division, or almost any date between. What it does not seem to be is recent, for it is similar in its dimensions and sinuosity to the major pre-modern earthworks ('trebs') which divide North Ronaldsay into three parts and Papa Westray into two parts, and the (Victorian) parish boundary omits the minor wiggles in its line while emulating its major sinuosity, which implies that the dyke pre-dates the (Victorian record of the) parish boundary by a considerable time.
It seems most likely to be either an important medieval or Norse land division with the potential to enhance understanding of medieval and earlier social organisation and hierarchies, or a major ritual monument with the potential to enhance understanding of social and ceremonial organisation at the heart of Neolithic and Bronze Age Orkney.