2004:1725 - COOLURE DEMESNE, Westmeath

Coolure Demesne crannog is situated in a small bay, at the north end of Lough Derravarragh, Co. Westmeath. It was recently investigated by a research project funded by the Heritage Council Archaeological Research Grants 2004 and by the Royal Irish Academy and Queen's University Belfast sponsored programme of radiocarbon dating. The project was carried out by a joint team from the School of Archaeology, UCD, the Department of Antiquities, National Museum of Ireland and the Underwater Archaeology Unit, DoEHLG. The project was a collaborative, multidisciplinary survey and excavation involving underwater survey, topographical survey, radiocarbon dating, dendrochronology (tree-ring dating) and specialist analyses of animal bones, wood, plant, macrofossil and insect remains. The results from all these studies have been significant, revealing that this artificial island dwelling has a long story of human endeavour spanning over a thousand years.

The crannog is currently a large (35m in width, 4m in height), tree-topped stony island situated in relatively shallow water (c. 12m depth) about 70m from the shoreline. It is overlooked by an impressive earthen ringfort on the shoreline. The project has revealed that the island was first built and occupied in c. 850 BC, in the Late Bronze Age, when a roundwood-post palisade was constructed around the southern edge of an island of clays and peats. It seems likely that then it was both a dwelling and a ritual platform, as several Late Bronze Age weapons and ornaments have been recovered from nearby in this small bay, particularly off the neighbouring Kiltoom shoreline. These may have been offerings to the spirits and beings of the water that were situated in the liminal space between this world and the otherworld.

Most surprisingly, the island was then reactivated during the transition between the pagan Iron Age/Early Christian period—Ireland's 'Dark Ages'. Dendrochronological (tree-ring) dates from the massive oak planks enclosing the southern and western part of the island show that they were taken from trees that had been felled c. AD 402. The use of an Iron Age/Early Christian fortified island site may be related to some significant regional political change and tribal migrations in the midlands in the 4th–5th century AD, traces of which echo down later into the historic period.

The early medieval crannog was then built on and occupied from c. AD 650, when roundwood post palisades were driven down to revet a mound of peat and stone. Landscape archaeological research indicates that the crannog may have been located on a significant regional political boundary—between the early medieval kingdoms of Mide and Tethbae. Coolure Demesne crannog may have been a lordly or even a royal site and certainly would have been one of the social and ideological hubs of life for the inhabitants of the district. Historical records suggest that the royal residence of a dynasty known as the Uí Fiachrach Cuile Fobair was here on the north shores of Lough Derravarragh and the crannog could at different times have been their summer lodge, their defensive refuge or their principal residence.

The early medieval crannog's occupation phases also resulted in the deposition of a dense midden of cattle, pig, horse and deer bone across the southern margins of the site, which may be evidence for high-status feasting activities.

Palaeoenvironmental studies indicate the consumption of oats and barley, possibly in porridges and gruels. Insect studies also indicated the presence of beetles and flies associated with human waste, suggesting that the edge of the island was used as their rubbish dump. The project's metal detector surveys also led to the recovery of many iron artefacts, including an iron axehead, billhook, nails and several arrowheads of a type used to pierce chain-mail.

The crannog was certainly occupied in the 9th and 10th century AD and the site may have been raised with a mantle of stones. The National Museum already has many artefacts from the site, most of which were taken by treasure hunters using metal detectors in the 1980s. They include a range of Viking artefacts (silver armlets, weighing scales, silver ingots) that were deposited on the site, probably obtained as loot and trade for Viking Dublin. There are also some artefacts, including a bishop's seal matrix and Anglo-Norman jewellery, that indicate some activity on the island right through to the 13th century AD. In modern times, the crannog had been largely forgotten, but the island continued to be used as a fishing lodge and for swimmers using the adjacent men and women's swimming areas on the shoreline prior to drainage in the 1960s.

For further information on this and other research projects, see the School of Archaeology's website at http://www.ucd.ie/archaeology.

School of Archaeology, UCD