Bulletin
1, 1995
The Project Design
by Martin Carver
Summary
The Tarbat Discovery Programme is designed to reveal the character and meaning of the ancient settlement at Tarbat and to display the findings in Tarbat Old Church so as to provide a permanent educational and entertaining destination for local people, schoolchildren, scholars and tourists.
The project design thus contains plans for the archaeological investigation of the site in its regional and international context (the research programme), and the refurbishment of the church its development as a display centre and museum (the management programme). This account deals mainly with the research programme, touching on the management programme only in so far as it affects, or provides an opportunity for, archaeological input.
RESEARCH PROGRAMME
Model of the Archaeological Deposit
The topography at Tarbat takes the form of two low hills with a buried spring system between them. The more easterly hill carries Tarbat Old Church and its churchyard, and the two hills are embraced by the enclosure ditch which probably continued to the sea along lines that have survived as property boundaries [Fig. 3 ]. The enclosure thus formed is D-shaped and encircles about 6 hectares of land against the sea at a point where the shore is sandy. Deposits increase in depth from a 250mm norm as they approach the buried spring, and some of the lowest deposits (west side) are expected to be waterlogged or preserved anaerobically. The deposits within the churchyard wall are artificially raised through burial to c.2m. Accumulation to a similar depth is met immediately adjacent to, and outside, the current churchyard wall.
The greater part of the area accessible to archaeological investigation is currently under cultivation. The top 250mm is scrambled by modern ploughing, and up to 1.2 m of earlier ploughsoil or dumping may be captured in the valley containing the water-course.
In Zone E, early stone and soil features survive immediately beneath modern ploughing which has touched them from time to time. Further north, in Zones D and F, the accumulation of later soils is sufficient to protect early features from plough-damage. Archaeological access to the churchyard (Zone B) is currently denied, since it remains in use for burial.
The deposit-model suggests that high yields of information are currently available and also most vulnerable in Zone E, east of the road to Rockfield. Here there are the foundations of stone, timber and (probably) turf buildings, with a large and well-preserved assemblage of animal bones. Although not yet dated themselves, these features lie within the enclosure which is likely to have been in use from the 2nd century to the 11th. To the north of this area (Zone D), the topsoil deepens, and such features, if they continue, should be even better preserved.
Zone J, which is now largely built up and has not been evaluated, is likely to have been a key area for the ancient settlement too, and particularly for its maritime activity. Zone A, the church, and Zone B, the churchyard, are likely to have received the main Christian investment. These zones have not been evaluated beyond what is known of the church building (see Stage 4 above) and from information from grave-diggers who encounter subsoil at 6-7 feet (about 2 metres). Any opportunity to obtain a stratigraphic sample from each of these three zones is important for the completion of the evaluation.
Research Agenda
Broadly stated, large scale settlement excavations relating to any period have yet to happen in this part of Scotland. Virtually any attempt at a definition of the material culture sequence will be welcomed, for itself and to the extent that it will empower reconnaissance and evaluation exercises on a regional scale.
The Tarbat evaluation was initiated, however, in the more specific context of the Early Historic period, here defined as 300-1100 AD, in which the origins of territorial and social units, and their political strategies and interactions, are being sought. Specifically, the political affiliations of kingdoms are thought to be expressed by the selective use of fortified sites, mound burial, monasteries and beachmarkets.
The research agenda also seeks evidence for the agricultural economy, and the organisation of production, especially as expressed through animal bone and for the cultivation of cereals and their storage as surplus. It is also believed that social systems and contacts with other communities will be revealed from the extraction and production of metals, and the manufacture and distribution of metalwork.
Thus, although the research agenda for Early Historic Scotland is still very broad, the Tarbat site has the capacity to address a surprising amount of it.
Research Objectives
The aims of the archaeological research programme are (1) to reveal the date, purpose, and social, economic and ideological character of the early site at Portmahomack and establish its historic context; (2) to reconstruct the settlement for experimental purposes; and (3) to leave a permanent educational facility at Portmahomack as a legacy of the research programme.
Research Design
The basic form of the Tarbat site is a rectilinear enclosure 6 hectares in extent fronting on to a beach bordering the Dornoch Firth. Within the enclosure are two low hills, one to the west and one to the east. Between them runs a subterranean water source fed at least partly by springs. The easterly hill carries the church of St Cholmag (Colman).
The deposit model shows that a substantial number of the objectives on the research agenda are within reach. The date of the ditch deposits (2nd-6th century AD) suggest that a fortification enclosing 6 hectares was in use between the time that the Picts first enter recorded history (3rd century AD) and the time of their exposure to Irish Christianity (6th century AD). The date and character of the sculpture suggest a monastic establishment receiving influence from both Irish and English sources. This is reinforced by the dedication of the church which still stands. The date and character of the Viking period hoard suggests a trading establishment in contact with France in the 9th century.
The present church contains a sequence within its fabric which began at least as early as the middle ages. It is likely that the crypt had cut through a burial ground of the Pictish period, disturbing a number of Pictish monuments and memorials [Figs. 5-8]. In the way of Christian sites, especially with churches which retain an ancient dedication, the early ritual centre is likely to lie beneath the present church.
The settlement examined non-destructively during evaluation has offered evidence for a building, a souterrain, and outdoor ovens or hearths. The character of the settlement emerges most clearly from its plan. Over much of the southern part of the enclosure, the plan is comprehensible and obtainable by stripping, cleaning and mapping, without detailed excavation. There is a rotary quern from the building. There is slag and a mould from the hearth area. The site is notable for the quantity and good preservation of animal bone which has the potential to report not only on diet but on social structure.
For the early medieval period, therefore, the site emanates strong signals of a rich and informative sequence.
The trial excavation nearest the church (Int.8) also demonstrated the presence of medieval pottery associated with agriculture and some rudimentary structures. Beneath the building in Int.7 there were traces of criss-cross ploughing. There is therefore some evidence for a prehistoric and medieval context for the early medieval sequence.
About half of the enclosure (i.e. Zone J) is presently inaccessible because it is occupied residential land. The area of the present churchyard (Zone B) is also inaccessible, since it remains in use and dedicated to the owners of lairage.
The research design applied to the Tarbat site has four elements:
- Investigation of the church site to confirm the fabric sequence and the existence of a Pictish burial ground.
- Excavation of a large sample of the settlement in plan, with selective full excavation of structural features likely to belong to the Early Historic period. The assemblage collection strategy is to include a strong emphasis on animal bone. The excavation sample should include the defences and be sited as near as possible to the church and the spring line.
- Mapping of the remainder of the enclosure and sample areas outside to be continued using calibrated geophysical survey and sample areas as they become available.
- Initiation of a regional survey, beginning with the Dornoch Firth area (Area A in Fig. 2), and continuing with structured surveys in the areas of Cromarty Firth, Moray and Inverness (B-D on Fig. 2).
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Last updated 10 October, 2003.
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