Publication Account
Date 2007
Event ID 587049
Category Descriptive Accounts
Type Publication Account
Permalink http://canmore.org.uk/event/587049
NG31 1 RUDH' AN DUNAIN
NG/396160 (visited 20/4/63 and in 1986).
This unexcavated promontory semi-broch is a classic site of its type and consists of a simple, gently curved wall barring the neck of a short, high cliff promontory in a very wild and remote part of south-west Skye. There is an abandoned two-storeyed house nearby (inhabited by the Macaskill family until about 1850 [4, 185]), and a Neolithic chambered tomb a few hundred yards away which was excavated by Sir Lindsay Scott in 1931 [4]. Scott also explored the nearby cave in 1932 [5] with results that probably have a bearing on the date of the Iron Age promontory fort (below). The name 'Rudh' an Dunain' is applied to the large promontory south-west of the site and means 'promontory of the fort'.
Situation
It is worth summarising Scott's comments on the remoteness and difficulty of access of this area [4, 132-33]. Contrary to what one might conclude from the presence of the two large prehistoric monuments, the inhabited cave and the abandoned house it is not easy to reach the small cultivable area on which they stand. Because the rugged, high Cuillins mountains lie immediately behind the site, and come down to the shore of Soay Sound to the east, the land approach involves a walk of three miles along the east shore of Loch Brittle, which itself is reached, from the head of Loch Harport, by way of the narrow pass of Glen Brittle. Coming by sea is not much easier because of the exposed nature of the Rudh' an Dunain (Scott gives details of possible landing places [4]: there is a boat port at the exit stream from Loch na h'Airde). The only cultivable ground nearby is the shallow valley running for just under half a mile west-south-west to Loch na h'Airde, a short distance north-west of the promontory fort.
Description
Although unexcavated this promontory semibroch could be providing important evidence both for the dating of its type and for the significance of semibrochs in the evolution of the broch type, as is explained below. Its full excavation is highly desirable.
The wall of the structure is fairly well preserved and is certainly not a “ruined ring” as thought by Childe [3, 198]; the diameter of a circular building of which this wall was a part would be something like 40-45m (up to 150 ft) – two-and-a-half times the size of the average broch. The fact that the wall narrows considerably as it approaches the cliff at the north-east end (furthest from the doorway) appears to confirm that the wall was never much longer than it is at present. Of course a huge amount of the cliff would have to have disappeared over the last two-and-a-half millennia if the structure was once a complete ring.
The entrance in the convex outer wallface – which has a pronounced batter – is near the right or south-west end and is 3.6m (12 ft) from the high and sheer cliff edge; it is just over 3.66m (12 ft) long and filled with rubble. Its lintels have disappeared but the door-frame is visible 1.14m (3 ft 9in) from the outside, where there are two well-built, opposed rebates in the walls; the bar-hole is not visible.
In the inner face, a short distance to the left of the inner end of the entrance (looking inwards), is the door to the mural gallery which runs along the rest of the wall to the opposite edge. The left side of this door is continuous with the end wall of the gallery which thus stops several feet short of the main entrance. One lintel remains over the door but none are visible over the gallery itself. However its walls rise well above this lintel to the wallhead, which is here 10-12 ft (3.0-3.6m) high above the level grassy surface outside; thus an upper as well as a lower tier of gallery must be preserved. A fine ledge scarcement 9 in (25cm) wide is preserved on the inner wallface; it runs along more or less level. It is not clear whether this ledge included the lintel over the doorway to the gallery but it seems probable.
The space enclosed by the drystone barrier is now quite small, measuring about 250 sq yds., but the area of the promontory may have been reduced by cliff falls since Iron Age times. Very large angular rock fragments can be seen under water below the cliffs.
Structural analysis
It has been noted before that, although the promontory defence is a simple curved wall, its hollow construction is of equal sophistication to that found in the broch towers [3]. The entrance passage is of standard broch design and the wall to the left of this appears to have two continuous, superimposed galleries in it (Levels 1 and 2). It is reached by a doorway from the interior of which the front lintel would probably once have formed part of the scarcement on the inner face. Doubtless there is a stair to the upper levels just to the right of the door but no steps are exposed.
No doubt there was once a chamber over the entrance passage and a void over the gallery door, both facing inwards, but nothing of these is preserved. However the fact that the wall has such a shallow curve means that the scarcement cannot have supported a two-storeyed wooden roundhouse in the interior and it must have had some other purpose. In this way Rudh' an Dunain is sharply distinct from the round towers and from D-shaped semibrochs like Dun an Ruigh Ruaidh. Some further comments on its probable age are in 'Significance of the site' below.
Excavations in the cave in 1932 [5]
There is a small cave in the cliff face of the raised shore-line about 500m east of the fort (c. NG/400163) and this was explored by Scott in 1932. Under some slabs fallen from the roof was a homogeneous deposit of fine, peaty earth resting on a thin layer of sea sand; traces of human occupation were found at all levels in the earth.
Essentially the cave seems to have been used at two separate periods in prehistoric times, and one would expect that these occupations appear to correspond with the occupations rep-resented by the two large ancient monuments nearby – the Neolithic chambered tomb and the Iron Age promontory fort. No domestic hearths were found so these occupations seem to have been by specialised workers associated with the communities concerned, and this is confirmed by the debris. The cave was excavated in square or rectangular trenches and, since no stratification could be observed in the earth deposits, these were divided into four arbitrary spits or levels [5, Pls. III and IV); these were labelled A-D from the top down. However considerable signs of disturbance from later levels into earlier ones were seen.
At the base of the earth, immediately above the sand, were found sherds of early Bronze Age Beaker pottery [5, fig. 5 and 6] together with abundant refuse of stone-knappers’ activities [5, fig. 1] Higher up were abundant signs of iron-smelting including a furnace built of stone slabs with quantities of slag around it [5, figs. 2 and 3]. A small number of Iron Age sherds were evidently linked to this smelting activity [5, fig. 7]. One of these is a fairly clear example of a carinated rim sherd of early Iron Age type, datable to the 7th and 6th centuries BC at, for example, Bu and Quanterness in Orkney (sites HY20 4 and HY41 5).
Tylecote [8] considers that the furnace was for smelting iron ore and offers a reconstruction of how it may have worked. A small amount of slag was found in the furnace but most of it was found in a heap on the north side. Although Sir Lindsay Scott gave the artifacts from his excavations at Rudh’ an Dunain to the National Museums of Scotland, a search on behalf of the author in 2003 failed to find any of the slag. The slag was of the "typical fayalite-magnetite type." The remains of a pinewood shovel were found nearby which he thought was probably used for shovelling charcoal.
Significance of the site
It seems reasonable to associate the two periods of major activity inside the cave with the two large prehistoric structures close by. Thus, although a chambered cairn of this type was almost certainly built and used in the early Neolithic period, this one was re-used in the early Bronze Age judging from the Beaker found at an upper level in it [4, 198]. The Beaker period lithic workshop in the cave fits with this.
Since the promontory fort has not been excavated its connection with the establishment of an iron smeltery in the cave, evidently in early Iron Age times, must be regarded as more tentative but it seems highly likely. This hypothesis is strongly supported by the appearance of extensive iron-working at Jarlshof in Shetland at the same early period (site HU30 1: 64-65].
The conclusion seems to follow that this promontory semibroch belongs to the early Iron Age and is also strongly supported by the evidence from Clickhimin in Shetland. A reassessment of the nature of the 'blockhouse' at that site, and of the associated pottery and artifacts, makes it extremely probable that that building is also a form of promontory semibroch which was constructed towards the end of the early Iron Age period, perhaps in the 6th or 5th centuries BC (site HU44 1, 89-115). The appearance of all the basic features of broch architecture in Atlantic Scotland at this early date is of great potential significance.
Rudh’ an Dunain and the two other very similar sites – Dun Grugaig, Skye (NG51 1), and Barra head (NL58 1) – show rather clearly that the high hollow wall was not originally designed as a protection for the multi-storeyed wooden roundhouse, which is what the tower broch seems to be. The curvature of their walls is much too shallow and the scarcements here must have supported some kind of two-storeyed range of buildings along its rear wall, as Hamilton envisaged at Clickhimin (site HU44 1).
Iron Age pottery from the cave
The probable early Iron Age rim sherds are described in Appendix 1. Broadly there appear to be two classes of Iron Age sherds among the Scott collection in the National Museums (in which there are hardly any rim sherds). The first group is similar to the Everted Rim ware found on Tiree – namely fairly thin sherds of plain, buff to buff-grey, sandy-textured hard ware with fairly smooth external surfaces, the cross-sections tending to be two thirds grey with the outer third buff; there are many tiny pits as if vegetable matter tempering in the clay has been burned during firing. The second group of sherds is thicker (8-12mm) and of similar fabric but the ware is grey-brown throughout with many small, black stone grits.
Sources: 1. NMRS site no. NG 31 NE 1: 2. RCAHMS 1928, 144, no. 483, and fig. 296: 3. Childe 1930, 77: 4. Scott 1932, 185: 5. Scott 1934b: 6. MacKie 1965, pl. XVIII, upper, and XIX, left: 7. MacSween 1984-85, 51, no. 60 and pls. 14 and 15: 8. Tylecote 1962, 195-97.
E W MacKie 2007
