The circular earthwork, measuring approximately 30 metres in diameter, revealed itself to be more complex than initially expected. Its surviving bank, still rising a metre above the current ground level in places, encircled a substantial ditch that had been carved into the landscape centuries ago. When the team carefully excavated sections through this ditch, they found it had a distinctive U-shaped profile, averaging 4.2 metres wide and 1.5 metres deep, though time had filled much of it with material that had gradually slipped from the surrounding bank.

The bank itself told its own story of construction; it was formed from redeposited subsoil, almost certainly the upcast earth from when the ditch was originally dug. Within this earthen rampart, the excavators discovered some telling artefacts: two whetstones and part of a rotary quern, everyday objects that hint at the lives of those who once occupied this site. The interior space yielded a scatter of post-holes, though frustratingly, these didn’t form any recognisable pattern that might indicate the layout of buildings or other structures that once stood here.

Perhaps most significantly, a single sherd of medieval pottery recovered from the ditch fill has led Gahan to propose that this isn’t a typical ringfort at all, but rather a ringwork castle dating to the 12th century. This distinction is important; whilst ringforts were primarily Irish defensive homesteads that proliferated during the early medieval period, ringworks were Anglo-Norman fortifications introduced after the invasion of 1169. If Gahan’s interpretation is correct, this monument at Ashfort represents not indigenous Irish construction, but the military architecture of Norman colonisers establishing their control over the Limerick landscape.