Excavations on the Tarbat Peninsula: Cnoc Tigh (Iron Age Round House)

by Oskar Sveinbjarnason (University of Aberdeen)

The excavation started as planned on the 22nd June. A 15m long trench and 10m wide was opened over the northern part of the dun. It took 2 days to open up the area (gorse removal and grass) and as the surrounding field was under crop, a JCB was not able to access the site and speed up the opening. It soon became apparent that the site has been largely robbed of stones, likely during the 19th – 20th Century, possibly to make the enclosure which sits on top of the dun. The quarry holes can still be seen. It was a hard task to plan and remove this later enclosure, mainly due to the amount of rubble and the fact that the enclosure was little more than tossed up earth and stone bank (we can firmly assume that this is not the Castle Corbet) and blended in with the dun itself.

Picture showing the surviving outer dun wall. The rubble to the left is a collapse which hid this outer wall face.

In the trench the outer dun wall face was harder to find than we expected and is it due to the large amount of collapse from the dun wall core outwards and collapse from the enclosure on top of it as well. It was towards the end of week 2 when we finally figured out where the outer dun wall was located and which made the site nicer and easier to understand.

The dun wall turned out to be a complex construction with multiple stages of construction now visible. Initially it seems to have started out as a round house with about 1.5m thick wall. Up against this wall, additional 2.5m of extra wall was added, making the wall about 4m thick.

Aerial view of Cnoc Tigh…

…and aerial view with interpretations.

The interior wall face took some time to find, mainly due to the amount of rubble on top of it. Once we managed to get through this rubble (from enclosure), a possible demolition layer was encountered. This layer was up against the inner wall face and contained few pieces of burnt wood. Underneath this demolition layer a charcoal floor was uncovered and which appears to contain sand layer underneath. However, under this sand layer another occupation layer was encountered and extended down to the natural soil. At a quick glance the occupation history of the site appear to starting with a construction of a round house (which wall faces belong to each period remains to be analysed). At some point the site may have been abandoned (sand layer) and then re-occupied (charcoal layer) before final decommission.

Picture showing the inside of the round house

Picture showing the entrance into the house

In the western part of the site a narrow (about 1m wide) entrance way was uncovered and seems to contain part of the floor layer from the interior of the house.

Picture showing the stratigraphy inside the dun

The black layer (see picture above) is charcoal and may belong to a re-occupation period. Underneath is a light coloured sand (windblown) which may represent the abandoned phase and below that is dark brown thick layer which seems to be the first occupation of the house. Unfortunately, no artefacts were found during the excavation and the hearth of the building should be few meters to the south of our excavation trench.

During the open day about 60 people came for guided a tour which is pretty good. However, some number of visitors has visited the site nearly every day. Two primary schools Also came to the site and the children got an introduction and first hand experience of what it is to be an archaeologist. They seemed to have liked it a lot and few returned later along with their parents or, in once instance, grand-parents. Finally, Oskar and Leaf visited the Tain Royal Academy and had a demonstration for the teenagers on the project and the tools we have and what we find.

C14 Carbon Dating Results for all the digs on the Tarbat Peninsula 2013/14