Celtic Connections and Crannogs: A new Study of Lake Settlements Across the Irish Sea

Crannog on Lough Youn, Northern Ireland. Photo: N. Whitehouse

This three year, AHRC funded project ‘Celtic Connections and Crannogs’ (2015-2018) is led by Prof Tony Brown (University of Southampton, University of Tromso, Norway) with CO-I’s Prof Pete Langdon (Southampton), Dr Andy Henderson (Newcastle), Dr Finbar McCormick (Queen’s University Belfast) and Prof Nicki Whitehouse (Glasgow).

A large team of researchers are also involved including Dr Maarten van Hardenbroek (Newcastle), Dr Kim Davies (Bournemouth), Dr Helen Mackay (Durham), Dr Emily Murray (QUB), Dr Phil Barratt (Glasgow/Nottingham), Dr Katie Head (Plymouth), Dr Tierry Fonville (Southampton). The AOC Archaeology Group is also involved through Dr Graeme Cavers and Dr Anne Crone.

Project background 

Around 3000 years ago communities in Scotland & Ireland started building islands called 'crannogs' in lakes & mires, a practice that in places continued into the Medieval Period. Why & how did these sites fit into the emerging Celtic landscapes we still see today? Crannogs show a distinctly westerly distribution being absent in England, with one in Wales, but common in Scotland (400) & Ireland (1500). Being under water these sites can have remarkable preservation of perishable artifacts, but because they are rarely in the path of development few have been excavated, however, many are under threat from erosion, pollution & natural decay. The recent discovery of a crannog with near-perfect preservation of artefacts due to road construction at Enniskillen (Drumclay) & another superbly preserved wetland village in Dumfreis & Galloway (Black Loch of Murton) offer rare glimpses of their archaeological potential & provides a unique opportunity for this project. Although crannogs can be found from the Scottish Islands to the SW of Ireland the central point in the distribution is the North Channel of the Irish Sea, separating Dumfries & Galloway from Antrim & Down. There are many cultural links between these regions particularly in the Iron Age & early Medieval Periods. Was Medieval Christian and/or noble connection founded upon earlier Iron Age cultural links & is this reflected in vernacular traditions including crannog construction? In order to answer these questions & explore the common lake-settlement heritage we need to know more about the chronology, longevity, intensity of use & environmental context of these enigmatic sites. The fact that in both areas their construction spanned over two millennia suggests there is no single stimuli for construction, however, indications of parallel chronologies may have implications for cultural, political, symbolic & environmental stimuli.

This project takes to a new level previous research by the applicants which developed a new methodology for 'remote sensing' crannog construction & inhabitation through the analysis of lake sediment cores. This involved a multi-proxy approach utilising pollen, diatoms & insects which relied on the inevitable disturbance to the biology of small lakes caused by crannog construction/use. This project will go far further by applying these techniques alongside a new generation of bioarchaeological methods, particularly geochemistry, lipid biomarkers & DNA metabarcoding in conjunction with archaeological excavation, landscape survey & community involvement. A major limitation of previous work was that none of the crannogs remote sensed were excavated.

One of the most variable aspects of crannog archaeology is longevity of use. Recent excavation at Cults Loch (SW Scotland) suggests it may have been in use for no more than half a century with construction in pulses, whereas indications from Drumclay suggests it may have been occupied for several centuries. An allied question is the intensity of use - were they dwellings & if so used seasonally, episodically or permanently? It is clear that longevity & intensity are key variables but since only a few crannogs will ever be excavated we need additional estimates from unexcavated crannogs. Site ages will be established using 14C AMS dating from lake cores, volcanic ash & tree-ring counts. Improvements in crannog dating each side of the Irish Sea will have important implications for understanding the stimuli for crannog construction since correlation may relate to common environmental conditions, especially under the unstable climatic conditions of the later prehistory & the sixth century AD. Although primarily a survey & environmental project, material culture will be compared as part of the survey element & partnership with excavations. Material culture from structures to portable artefacts are invaluable for understanding the cultural context of crannog use from agricultural implements to religious items.

There are around 1500 known sites in Ireland and 400 in Scotland (but only one in Wales and none in England). Many were constructed during the Iron Age, ca. 2500 years ago and used up until the Medieval Period, but some examples are even earlier, being dated to the Bronze Age and even a few are known from the Neolithic. As a settlement type, therefore, they have a very long history. Improvements in crannog chronology each side of the Irish Sea will have important implications for understanding the stimuli for crannog construction since correlation may relate to common environmental factors in this region, especially under the unstable climatic conditions of the later prehistory and the sixth century.


The project set out to re-examine crannogs as both a cultural and environmental phenomenon that link Iron Age and Medieval communities of SW Scotland and N Ireland. We still know relatively little concerning their role in society – were they long-lived or restricted to a short period of use, permanent (year-round) settlements, seasonally occupied or ‘boltholes’? Were they functional (storage, craft manufacture) and/or ritual sites or did they have a defensive/protective function for the elite? The recovery of several high-status Christian artefacts has also raised questions around the role of crannogs in the spread of Christianity through the Celtic world, in a region with almost (but not total) apparent isolation from Roman Britain and the rest of the Roman Empire, to the south and east.

To answer these questions and explore the cultural significance of these Celtic communities, we needed to understand the chronology, longevity, intensity of use, form, function, material culture and environmental context of these sites. This project aimed to derive this information from the crannogs themselves through archaeological excavation but also by tracing the signal of the crannogs in the surrounding lake sediments through palaeoenvironmental techniques. It is clear that longevity & intensity are key variables but since only a few crannogs have been and will ever be excavated we need additional estimates from unexcavated crannogs. This project set out to use these new techniques to improve understanding of crannogs and their usage.

Additional information on the project

Publications from the Project

Brown, A.G.; Fonville, T.; van Hardenbroek, M.; Cavers, G.; Crone, A.; McCormick, F.; Murray, E.; Mackay, H.; Whitehouse, N.J.; Henderson, A.; Barratt, P.; Davies, K.; Head, K.;  Langdon, P.G.; Alsos, I. & Pirrie, D. Accepted, 2022. New integrated molecular approaches for investigating lake settlements in north-western Europe. Antiquity.

Brown, A.G., Van Hardenbroek, M., Fonville, T., Davies, K., Mackay, H., Murray, E., Head, K. Barratt, P. , McCormick, F., Ficetola, G.F., Henderson, A.C.G, Crone, A., Cavers, G., Langdon, P.G., Whitehouse, N. J.,  Alsos, I.G., Pirrie, D. 2021. Slaughter and feasting revealed by DNA and lipids from Celtic Islands (Crannógs). Nature Scientific Reports.

Crone, A.; Cavers, G.; Allison, E.; Davies, E.; Hamilton, D.; Henderson, A.; Mackay, H.; McLaren, D.; Robertson, J.; Roy, L. and Whitehouse, N. 2019. Nasty, Brutish and Short? The life cycle of an Iron Age round house at Black Loch of Myrton, SW Scotland. Journal of Wetland Archaeology 18 (2) 138-162. 

Mackay, H.; Kimberley Davies; Jack Robertson; Lynne Roy; Ian Bull; Whitehouse, N.J.; Anne Crone; Graeme Cavers; Finbar McCormick; Antony Brown; Andrew Henderson. 2020. Understanding Iron Age daily life: faecal biomarker evidence for roundhouse use in a Scottish wetland village. Journal of Archaeological Science 121, 105202.