Benbecula, Loch Olavat, Dun Aonais

Dun Aonais, Loch Olavat.

Some 500 yards from the north-west end of Loch Olavat, and about 40 yards from it s western shore, is Dun Aonais, the third dun in this loch. It occupies the whole of a small island some 30 yards in diameter and rising 9 feet in height, which lies 300 yards north-west of Dun Ruadh (NF75SE 8). The sloping margin of the island for the entire circumference is covered, for a width of at least 15 feet and for a depth of about 2 feet, by a mass of stones, evidently the ruins of a wall built at the edge of the water. But so thorough has been the destruction wrought here that no building can be seen. On the summit of the island, about 6 feet above water level, and smothered by vegetation, are the ruined walls of a building composed of two oblong compartments placed parallel to and communicating with each other. The longer axis runs nearly west-north-west and east south-east . The western compartment, the larger, measures internally 35 feet 3 inches in length by 17 feet in breadth , and the other 27 feet in length by 12 feet 6 inches in breadth. The gables are not in line, but the larger chamber stands more to the north, its northern gable projecting 16 feet beyond the corresponding gable of the eastern chamber. Though hidden by brambles, bracken and foxgloves, the wall stands about 2 feet in height on the inside, and is about 3 feet thick, the divisional wall which is most clearly defined being 2 feet 9 inches thick. The entrance is placed about 4 feet from the northern end of the western wall of the larger chamber, but is too broken down for measurement, and the door between the rooms, which measures 4 feet in width, is placed 3 feet from the northern end of the eastern room. On the opposite wall, some 6 feet from the north end, a portion of the south jamb of a window or recess is noticeable.

The dun is reached over a causeway now spread over a space of 8 feet, but probably originally about 5 feet wide on the top, which partly submerged, is carried in a north-westerly direction for about 50 yards, where It reaches the present shore. From this point it is continued some 25 yards on dry land, making a curve towards the north-west. It resembles the causeway to Dun Aonais (NF87SE 4), in as much as it is now partly above water-level, which fact is further testimony to the lowering of the level of the water in times posterior to the occupation or erection of these duns.

RCAHMS 1928, visited 9 July 1915.

OS map: South Uist xlvi.

NF 7968 5125 Dun Aonais, Loch Olabhat. Large artificial or modified island, or 'high cairn crannog'. The causeway is well built and composed of very substantial boulders. The main part of the dun is filled by two parallel rectilinear structures with slightly rounded ends, running NW-SE. The walls are stone and well built. They are separated by a shared wall, and joined by a doorway towards the northern extent. The NE structure appears to be a building, 19 x 11m, with two flared stone-built windows in the outer wall, facing onto the loch. The other structure, 24 x 12.5m, may be another building, but it seems more likely that this served as a courtyard to the inner building.

To the NE is another smaller drystone rectilinear structure, internally 7 x 4.5m, though it is largely obscured by rubble and undergrowth.

Sponsors: Universities of Glasgow and Sheffield, King Alfred's College.

J A Raven and M Shelley 2003