Publication Account
Date 2007
Event ID 587232
Category Descriptive Accounts
Type Publication Account
Permalink http://canmore.org.uk/event/587232
NM54 1 AN SEAN CHAISTEAL (‘Ardnacross’)
NM/5510 4988
This broch in Kilninian and Kilmore is in an unusual situation for a western such site, standing as it does on flat, modern farmland next to a short, steep rocky bluff about 9m (30 ft) high and overlooking the Sound of Mull (visited 4/6/64 and 9/10/89). The bluff is probably the edge of a raised beach and it leads down to the rocky shore.
Description
Level 1. The building is almost circular and the exposed entrance passage – facing north-west up the coast – is 4.1m long and 1.1m wide at the outside. There are two lintels still in position (one in situ over the door- frame) and two built door-checks are apparent 1.4m from the outer end. The bar-hole and -socket (on the left) are just visible immediately behind the checks. In 1964 the front lintel had fallen forward but by 1989 it was back in position, its lower face some 20cm below that of the one at the door-frame. It is a large slab, almost a truncated triangle in shape and doubtless originally stood on edge like others in this position. The passage widens to 1.5m behind the checks and narrows again to 1.1m at the inner end. A pit in the wallhead to the left of the entrance may mark the position of a guard cell; there is nothing comparable visible on the right side.
Level 2. Since the inner lintel over the entrance is much thinner than the outermost one it seems likely that there was a hollow in the wall above the whole length of the passage (up to the outermost massive one) – an inwards-facing chamber in fact. Indeed it can be seen that the side walls of the passage – built of large, flattish stone slabs – rise about a foot above the lintel at the door-frame and ought to be the base of the walls of the chamber above. However no sockets for torn-out lintels are apparent.
There are traces of what appears to be a mural gallery on the wallhead from about 8.30 to 9 o’clock and also [2] from about 12.30 to 2 o’clock. In the former place it seems to curve inwards at 9 o’clock before disappearing under rubble. The fragment of gallery is about 1.2m (4 ft) higher than the entrance lintel so it ought to be an upper tier even though it is only about 1.8m (6 ft) above the outside ground surface at this point. The interior is too full of debris for any scarcement to be visible; it is probably buried.
At about 1 o’clock a lintel on the wallhead is visible, at about the height of that over the entrance; it seems to cover a stretch of gallery and the inner face of this is marked on the plan. If the ground on which the broch stands is flat the wall may be about 3m (10 ft) high on the landward side.
There is a possible outer wall on the north side, running towards the beach; the broch entrance is close to it so it may be an outer defence for that.
Discussion
The unusual situation of this broch on flat ground recalls solid-based brochs on the west coast like Dun Troddan and Dun Telve, and it may be that An Sean Chaisteal is one of those, a more advanced form of tower built more confidently on low-lying ground. The relatively thick wall (below) is appropriate for a solid-based broch.
Dimensions: from 6-12 o’clock the overall diameter is about 18.0m (59 ft), the wall thickness (at the entrance) being 4.12m (13.5 ft). From 9-3 o’clock the overall diameter is 18.61m (61 ft), the internal from 7.93 - 8.24m (16-27 ft). The wall proportion on the latter axis is therefore about 55%.
Sources: 1. NMRS site no. NM 54 NE 4: 2. RCAHMS 1980, 90-1, no. 165 and fig. 89.
E W MacKie 2007
