The monument consists of the remains of a small castle, possibly originally a dun, situated on an islet off Calvay, on the S side of Loch Boisdale.
The islet on which the castle sits was formerly connected to Calvay by a causeway, but this has now almost completely gone. On the landward side a curving wall of irregular thickness and of drystone masonry appears to be the earliest element of the remians: it may be part of a dun. The W, N and NE sides of a polygonal enclosure are
formed by badly mortared walls of rough rubble, in places
incorporating substantial stretches of earlier, unmortared, walling.
The fortification has maximum overall dimensions of 30m SW-NE by 20m. A number of gun-slits are evident, particularly on the W side. There are two main internal buildings, both abutting and incorporating the outer wall. On the SW corner a small square structure some 4m by 4m externally may have been a low tower overlooking the approach from Calvay. On the N side is a bicameral rectangular block some 13m by 6m externally, possibly formed by the eastward extension of a smaller structure.
The remains are too ruinous to be certain about the
phasing of construction. The area to be scheduled consists of the whole of the small islet, above the edge of the tidal rocks: this coincides with the enclosure and its interior, as marked in red on the accompanying map.
We compile, maintain and publish a Schedule (a list) of monuments of national importance under the Ancient Monuments and Archaeological Areas Act 1979. Scheduling is the process of adding monuments to this list and affording them statutory protection. The aim of scheduling is to preserve sites and monuments as far as possible in the form in which they have come down to us today. Once a monument is scheduled, the prior written consent of ourselves is required for most works including repairs.
The information provided gives an indication of the cultural significance of a scheduled monument. The information is current to the date of designation or when last amended. This record is not intended to be a definitive account or a complete description of the monument(s) and the format of records has changed over time. Earlier, un-amended records will usually be brief and some information will not have been recorded.
Find out more about scheduling and our other designations at www.historic-scotland.gov.uk/heritage.