Dun Mhurchaidh

Excavations in Ardnamurchan by the Ardnamurchan Transitions Project began in 2006 and the project has excavated sites from the Neolithic, Bronze Age, Iron Age and post-medieval periods as part of our attempts to characterise the changing forms of occupation within Swordle Bay on the peninsula’s northern coast. The 2012 season, which ran 6–26 August centred on three sites: the probable Iron Age area of activity on top of the natural promontory of Dun Murchaidh (DES 2011, 94–95); the probable pre-clearance Swordle Township of Swordle Huel; and a possible Bronze Age cremation and associated feature identified in previous season’s work through fieldwalking and geophysics (site known as the BAFoF).

Dun Murchaidh. Five trenches were opened across the promontory to further investigate findings from the previous season of work. The trenches revealed the remains of two small sub-rectangular dry stone walled structures, one positioned at the entrance to the summit of the promontory, and the second further to the N, which appeared to have been cut into the natural slope, with a poorly preserved exterior crude cobbled surface. Both structures made use of the local topography and outcrops of bedrock. Several worked stones were recovered from the soil deposits associated with these structures, including burnishing stones and a hammerstone. Further evidence of the laid surface or paving found during 2011 was identified, although no further information was recovered to ascertain the function of the paving. A single posthole abutting a bedrock outcrop running along the W side of the promontory was also identified, together with a small hearth or area of burnt material cut into natural soil overlying sloping bedrock and opposite the posthole.

Archive: Highland HER and RCAHMS (intended)

Funder: Ardnamurchan Estate, Manchester University, Leicester University, Prehistoric Society, Royal Archaeological Institute and CFA Archaeology Ltd

Hannah Cobb, Manchester University

Héléna Gray, Manchester University

Oliver Harris, Leicester University

Phil Richardson, Archaeology Scotland

2012

NM 53366 70650 (Canmore ID: 346945) 12 July – 1 August 2015 The Ardnamurchan Transitions Project (ATP) has been excavating a range of sites in and around Swordle Bay since 2006 as part of a research and community orientated project investigating the long-term histories of occupation within the bay, through key moments of social transition from the Mesolithic through to the 19th century. The project has undertaken extensive landscape survey, geophysical analysis, environmental survey and test pitting to locate sites for excavation. As part of this work we have also undertaken preliminary investigations at the Iron Age promotory site of Dún Mhurchaidh in 2011 and 2012, and we returned to fully investigate this site from 12 July – 1 August 2015.

The potential of Dún Mhurchaidh was first noted in the 1970s by Highland Council Archaeologists, although it has seen no further investigations until the work of the ATP. The site was first examined by the project in 2011 when a total of ten test pits were excavated across the Dún, revealing a number of areas of archaeological activity. This included activity in the entrance to the promontory, and a possible metalworking area at the heart of the promontory, which was defined by a charcoal-rich deposit containing slag-like material, as well as a fragment of a shale-like bangle and a small glass or amber bead. The site was then further excavated in 2012. A total of six trenches were opened along the length of the ridge, specifically focusing on the entrance area, the potential ditch area, the potential metalworking area, as well as a trench at the N end of the ridge. This latter trench identified some anthropogenic activity, although the nature of this was not clarified. The potential metalworking area identified more metalworking and a flat paved stone area which was left to be re-excavated. The trenches on the southern portion of the ridge identified a portion of an ephemeral structure and, at the entrance to the promontory, a more substantial circular structure.

Following the above investigations, the character and sequence of the archaeology remained unclear, so the project returned to the site in 2015 to find dating evidence to confirm or challenge the hypothesis that the site may be Iron Age. The project opened five trenches along the length of the ridge; one trench (Trench 16) was located at the promontory entrance to investigate the northern extent of the circular structure, and a further two trenches (Trenches 13N and 13S) were located to the N of this, but still within the southern portion of the promontory, in order to understand activities in the initial, southern section of the promontory. Further along the promontory, a trench (Trench 12) was re-opened over the flat paved stone area identified in 2012 and this was subsequently extended to the N. A final trench (Trench 17) was opened at the northern tip of the promontory to help characterise the nature of the anthropogenic activity identified in 2012. Trench 17 found only very ephemeral evidence for activity at the N of the promontory, indicated by the presence of pottery, but no features could be determined.

Within the centre of the promontory, Trench 12 has now helped to begin to resolve the complex activities taking part in this location. It is clear that significant amounts of metalworking were taking place here, and the evidence from previous seasons suggests this dates firmly to the Iron Age. Combining the evidence from Trench 12 over two seasons and test pit four can now be seen as firmly suggesting the presence of a large sub-rectangular structure, c10 x 4m, with at least one entrance facing NW. Within this is extensive evidence of metalworking, including slag deposits, plentiful amounts of charcoal as well as potential evidence for shaleworking.

The role of the two platforms remains unclear, with no features being uncovered under the one (078) excavated this year. However, the discovery of the large pit [150] in the corner of the trench, which contains an iron deposit not yet excavated, raises the potential that this represents an Iron Age bowl furnace.

Further excavation of this feature and the floors uncovered this season are required to fully understand the complex sequence here. It now seems clear though that this represents a significant metal working site located very specifically on this promontory.

Moving to the southern portion of the promontory, Trench 13N and 13S built on findings from Trench 13, opened in 2012, demonstrating the presence of several returning walls abutting the natural bedrock which indicate the presence of two sub-rectangular cellular structures. These structures were probably both fairly ephemeral, and may be more like the construction of shelters with temporary roofs than the more substantial structure in Trench 12. The discovery of numerous burnishing stones in association with the structure in Trench 13N suggests activity associated with metalworking here too. Some of these stones may also represent the local ironstone and be directly related to the processing and preparing of material for smelting further up the promontory in the structure in Trench 12. One of the pieces of possible iron stone was deliberately polished on one side, potentially indicating a complex ritual involved in its preparation as it is not clear what functional purpose this might serve.

Within the southern part of the promontory, running along the W side of the promontory, along the bedrock, a likely drainage gully was located in all of the trenches, cutting the upmost floor layer in each, and containing two postholes, which related to the structures noted above. Finally, Trench 16 provided an excellent sequence, demonstrating the constructed surface layer associated with the structures in Trenches 13N and 13S was more recent than the circular structure at the entrance to the promontory identified in 2012. Further the structure is also probably Iron Age in date, as shown by the presence of slag in the fill of a cut sealed by the collapsed wall.

The work conducted in 2015 has helped resolve a number of questions that were posed at the end of the 2012 season, and a much clearer narrative has emerged for the site. Crucially, we can say with some confidence that this site does not fit, typologically, with other promontory forts from Iron Age Scotland. Indeed the lack of a ditch or defences of any kind suggest there was no defensive or fortified use of this site at all. Instead, the proliferation of metalworking and material culture associated with this, as well as the presence of a bowl furnace all point to metalworking being a key activity at this site. Further, the presence of several cellular structures, which would have impeded progress along the promontory, leading to a very large, likely subrectangular structure that was a focus for metalworking, with an entrance aligned with the W, and the setting sun, all indicate that a degree of ceremony, and ritual, defined

activities at this site.

Samples have been acquired for radiocarbon dating and funding is being sought to date this material. Meanwhile we can say with confidence that the presence of slag and iron working throughout indicates that the site is Iron Age, with multiple phases of activity. Bowl furnaces are usually associated with the Early Iron Age, which would place this as roughly contemporaneous with early Iron Age radiocarbon dates from the nearby site of Cladh Aindreis.

However, both the large circular structure at the entrance of the promontory and the bowl furnace in the central section of the promontory are the first deposits in a longer sequence of floors and structures, all associated with iron working, suggesting that this site may have had a long sequence of activity spanning the Iron Age. There is still much work to be done in post-excavation to unpick the full sequence and further excavation of Trench 12 will be needed to ensure the full suite of practices here can be dated and understood.

Archive: Highland HER and National Record of the Historic Environment (intended)

Funder: University of Manchester and University of Leicester

Website: http://ardnamurchantransitionsproject.co.uk/

Hannah Cobb, Oliver Harris, Paul Murtagh, Helena Gray and Phil Richardson – Ardnamurchan Transitions Project

(Source: DES, Volume 16)