Situated on a small promontory at Ardvasar, Dun Acardinon has to be visited by a somewhat circuitous route, as a direct assault along the coast is difficult (large rocks, cliffs etc.). Parking is available adjacent to the bus stop, from where you must walk on 100 metres to a road on the left labelled 'Knoydart'. Follow this short road to its end where a gravel path leads to a gate with a 'Please Shut Gate notice on it (blue marker).
Pass through the gate into rough pasture and either follow the clifftop or cut across directly to the dun (map below).
When I visited, in September, Dun Acardinon was so thickly clad in a mixture of hazel scrub and head-high bracken that I could not fight my way on to its summit; and if I had, I doubt I would have seen anything of interest.
The shore surrounding the fort is easily reached down a gentle grassy slope, and the best views are obtained from there. The fort is well defended by sheer cliffs, and as you walk around it, the huge cleft that almost splits the headland in half is apparent.
If you look hard, there is ample evidence of walling blocks, but again, they were well hidden behind a veil of brambles, bracken and other vegetation.
On the S side of the small bay lying immediately to the S of Rudha Dubh, is a rocky plateau standing some 25-35ft above the sea, and connected with the land on the W side by a narrow neck. It is of very irregular outline, being almost split in two by a deep gully running in from the seaward side. Known usually as Carn Breac, but sometimes as Dun Acardinon, its defensive character is clearly indicated by a stone wall, whose grass-covered mound, some 12ft in width and 3ft high, can be traced on the W side standing on top of the scarp of the hollow outside measuring some 12ft deep. A portion of the ground occupied by this wall has been levelled to form a potato garden, and a section of the wall is exposed. The remains of a wall, now 6ft wide and 2ft high, are seen on the edge of the cliff on the SW, and there are traces of a similar construction to the NE. At this place there is a small terrace lying outside and about 10ft lower than the wall, which has also been defended by a breastwork built on the edge of the rock. The dun measures about 136ft E-W and 87 ft N-S.
Dun Acardinon, the remains of a dun, as described by RCAHMS, except that the 'section of wall exposed' is a modern revetment on the edge of the potato patch.