Ireland Had a City Long Before the Vikings Arrived
Walk into any introductory lecture on Irish history and you will likely hear the same claim: that the Vikings founded Ireland’s first towns. Dublin, Waterford, Limerick, Wexford, all of them established by Norse settlers in the ninth century. The narrative is tidy. It fits the broader picture of Ireland as a land of scattered rural ringforts and monastic settlements before the Norse arrived and introduced urban life. A study published in the journal Antiquity at the end of 2025 put a significant dent in that story, backed by radiocarbon dating, aerial survey, and excavation.
At Brusselstown Ring, a hillfort in County Wicklow near Baltinglass at the southwestern edge of the Wicklow Mountains, researchers led by Dr. Dirk Brandherm of Queen’s University Belfast have identified what they describe as the largest nucleated settlement ever found in prehistoric Britain or Ireland. More than 600 suspected house platforms cover the hillfort’s interior, spread across 41 hectares within two widely spaced concentric ramparts. The site was occupied from approximately 1210 BCE to around 400 BCE, placing it in the Late Bronze Age and Early Iron Age, over a thousand years before the first Viking longship appeared off the Irish coast. This is not a minor revision to how we understand Irish prehistory.
The Scale of the Site
The numbers are striking. Ireland’s typical prehistoric settlement consisted of one to five dwellings. Brusselstown Ring contains, by current survey data, somewhere between 288 and more than 600 potential roundhouse platforms, depending on whether you rely on terrestrial survey or aerial photography. Aerial surveys from 2017 and 2022 identified more than 600 microtopographical anomalies consistent with house platforms, of which 98 lay within the inner rampart and 509 between the inner and outer enclosing walls.
The next-largest roundhouse agglomerations in prehistoric Ireland, at Turlough Hill in County Clare and Mullaghfarna in County Sligo, contain roughly 140 and 150 house remains respectively. The gap between Brusselstown Ring and the nearest comparable site is enormous. The total enclosed area of the site is 41.19 hectares just for Brusselstown Ring itself. The outer enclosing element extends further to incorporate the neighboring Neolithic enclosure of Spinans Hill 1, for a combined footprint of 131 hectares. Hillforts spanning more than one hilltop are exceptionally rare anywhere in Britain or Ireland, and even among the Late Iron Age oppida of continental Europe, typically dating to around 150 to 50 BCE, multi-summit enclosures of this kind are unusual.
The research was published in Antiquity and won the Prehistoric Society’s James Dyer Prize for 2025. It synthesizes two decades of existing survey data with new aerial photography, radiocarbon dating from the 2024 test trenches, and analysis of a potential water management structure that has no known parallel in any Irish hillfort.