Achadunan

A mound of sand and gravel rises 15' - 20' above the level of the cultivated haugh lands from which its base is separated by a 30' wide marshy channel which forms a semi- circle round its base. The mound is planted with trees and rises rather more steeply on the N end than to the S. Its W side seems to have been eroded and falls very steeply to the river bed so that the summit is now a narrow ridge 6' wide at most. Along the top of this ridge for a distance of 95', the footings of a wall of large boulders can be distinctly traced; this strip of walling is in line with a bank that borders the river channel on the haugh lands to the N and S, though interrupted by the channel already mentioned, which on the N carries a small tributary burn. Hence the "fort" may be (a) a glacial mound isolated by an older water course and traversed by a modern field dyke; (b) a fort on a natural mound, the W part of which has been washed away by the river; (c) a motte traversed by a later field dyke. Without excavation, it is impossible to decide between these possibilities.

Information from RCAHMS Manuscript.

This glacial mound rises some 6m above the general level of the gravel terrace on the SE bank of the River Fyne, 400m N of Achadunan farmhouse which probably takes its name from the fortification (en.1*). It is separated from the neighbouring haugh-lands by an impressive 10m-wide ditch which follows a semicircular course around its base. The mound itself is of narrow linear form extending over 28mfrom N to S, but much of the summit is as little as 1.5m to 2min width. Traces of walling, probably the remains of a later field-dyke, run along the line of the ridge. The existing summit-area is clearly insufficient to have served as a defensive platform, but whether or by how much the W flank of the mound may have been eroded by the river is difficult to ascertain without excavation. On the basis of the surviving surface-remains it is therefore difficult to determine whether the earthwork should be classified as a motte, though the landward ditch, which at the N carries a small tributary burn, appears to be an artificial work of medieval character.

RCAHMS 1992, visited September 1988