Evidence of medieval settlement discovered near Castlelost

Archaeological findings possibly dating back as far as 1,600 years have been uncovered at a Gas Networks Ireland project site in Kilbrennan.

Archaeological investigations commissioned by Gas Networks Ireland have revealed evidence of medieval life at a site in Kilbrennan, Westmeath, believed to date from between 400AD and 1400AD.

The discoveries include postholes, pits and a circular enclosure associated with a medieval field system. Artefacts recovered from the site include stone-lined cereal drying kilns as well as pottery, flint and clay tobacco pipes.

The site is along the route of the new Kiltotan gas transmission pipeline, crossing through the townlands of Kilbrennan, Collinstown and Oldtown. The pipeline, which has been laid by Gas Networks Ireland and is approximately 5.5 km in length, will transport gas to the Castlelost electricity generation plant near Rochfordsbridge.

The pre-construction investigations were carried out by Archaeological Consultancy Services Unit (ACSU) under the direction of Dr Rose Cleary, as part of Gas Networks Ireland’s code of practice for archaeology on all major pipeline works.

An Environmental Impact Assessment Report was required for the pipeline project, and the route was subject to surveys under license from the National Monument Services and supervision by the project archaeologist, Dr Cleary.

The geophysical survey took place in April 2024, and on-site works involving 56 test trenches were completed by November 2024, prior to the commencement of pipelaying. This, together with monitoring of the construction works, was completed by ACSU, alongside the construction crew, and ensured that archaeological features were protected during the project.

The majority of the site has now been preserved ‘in situ,’ while some features will be preserved ‘by record’, meaning full archaeological excavation by hand, samples taken and finds retrieved, registered and removed to an off-site location for preservation.

Post-excavation analysis including radiocarbon dating of charcoal and seeds and preliminary reports have been completed, with final reports expected to be submitted before the end of this year.

Speaking about how Gas Networks Ireland adheres to Government codes of practice in areas of potential archaeological significance before any construction works can begin, Gas Networks Ireland’s Senior Environmental Engineer, Maeve O’Reilly said: “Protecting Ireland’s archaeological heritage is an integral part of how we deliver our gas pipeline and infrastructure projects.

“We take our responsibility to safeguard the environment and cultural heritage very seriously. At all stages of the Kiltotan project, we coordinated the pipe-laying carefully with our archaeological specialists and local landowners to ensure that any findings uncovered were properly excavated, recorded and preserved in line with the national code of practice.”

The initial discovery in Kilbrennan was made in 2024 as part of a geophysical survey to identify potential archaeological features through changes in soil magnetism. The results of the first field survey found five previously undocumented archaeological sites, dating from circa 400AD-1400AD.

Project Archaeologist Dr Rose Cleary spoke of the find: “A gas pipeline crosses a modern landscape which has largely changed over time because of land improvements but can yield archaeological sites hidden beneath the ground.

“The archaeological input of pipeline construction aims to establish as much information on potential archaeological remains and reduce the risk of uncovering extensive and complex archaeological sites. Archaeological remains are invariably uncovered, and these are excavated and recorded for posterity providing a window into Ireland’s past.

The archaeological sites on the Castlelost project and the subsequent scientific analysis of the remains are an important part of the study of the historic landscape of County Westmeath.”

Archaeological Consultancy Services Unit’s Managing Director, Donald Murphy added: “Sites like these offer an extraordinary glimpse into Ireland’s past, showing how communities lived, worked, and adapted to their environment over the centuries. The careful excavation and recording of these finds ensure that the story of the site can be shared with future generations.”

The five separate areas identified were Kilbrennan 1 (field system), Kilbrennan 2 (kiln), Castlelost West 1 (pits), Castlelost West 2 (pits), and Oldtown 1 (ditches/field systems, pits).

Excavations at Oldtown uncovered a series of enclosure ditches dating to 1290–1400 AD placing them in the Anglo-Norman period of Irish history. The ditches may be associated with an extensive and complex settlement to the east of and outside the pipeline corridor.

Finds from the ditch fills included animal bones including cattle, horse and dog bones and charred cereal grains from mainly wheat and barley. These finds provide some insight into farming during the Anglo-Norman phase of Irish archaeology.

A site at Castlelost was also excavated, and pits dating 680–890 AD were recorded. Part of an iron buckle was found in one of the pits. For more information ‘Gas to Castlelost’ project please visit: Gas to Castlelost | Gas Networks Ireland