At Cloonlara in County Mayo, a circular earthwork once sat on a low rise above a wide sweep of pasture and bog to the south and south-west. A rath, to use the Irish term for a ringfort, is typically a roughly circular enclosure defined by an earthen bank and an outer ditch, and for centuries this one was a legible feature in the landscape, around thirty metres across and visible enough to be carefully mapped by Ordnance Survey cartographers in both 1837 and 1919. By the time the twentieth century was done with it, almost nothing remained.

The 1919 map already showed trouble: a quarry pit was cutting into the north-western quadrant of the enclosure. That quarrying continued and expanded as the century progressed, and the earthwork was gradually consumed. In 1992, ahead of construction work on the N5 Swinford by-pass, four test trenches were opened across the area to establish whether any trace of the enclosing fosse, the ditch that would originally have run around the outside of the bank, had survived below ground. The excavation, directed by Walsh and reported the following year, found no features or finds of archaeological significance. The site had been thoroughly erased. What makes this more than a simple story of loss is the immediate surroundings: a separate enclosure and a rath survive on an east-west ridge roughly 220 to 240 metres to the north and north-west, close enough to suggest that the Cloonlara site was once part of a small cluster of related early medieval activity in this part of Mayo.