At Lisduggan in County Waterford, a low earthwork sits on a gentle east-facing slope, easy to overlook and surprisingly difficult to categorise. What survives today is a single length of bank, roughly 19 metres long, overgrown and thickened over time by accumulated spoil. It rises to around four metres on its interior face and three and a half metres on its exterior, and beside it two large, shallow quarry scoops spread across the ground to the west, each roughly half a metre deep. These quarries may well be the source of some of that added material, though the full history of how the earthwork came to look as it does is not straightforward.

The enclosure has been interpreted differently at almost every stage of its recorded history, which is part of what makes it interesting. When the Ordnance Survey mapped the area in 1840, surveyors recorded an irregular D-shaped embanked enclosure, roughly 40 metres across in both directions, incorporating existing field banks along its eastern and southern sides. By the time a later edition of the OS map appeared in 1950 to 1951, the feature had been reduced in the record to a simple oval mound, its dimensions shrunk to around 30 metres by 20 metres. The most striking misreading came from the Reverend P. Power, who in his 1952 work on the placenames of the Decies, a study of the ancient territory covering much of County Waterford, classified the site as a motte. A motte is the steep, flat-topped mound characteristic of Norman fortifications, typically constructed in the decades after the twelfth-century invasion as a base for a timber tower. The Lisduggan earthwork does not fit that description. Its profile is too irregular, its form too ambiguous, and subsequent archaeological assessment has firmly set aside Power's classification. What it actually represents, whether a prehistoric enclosure, a ringfort variant, or something else, remains less certain than what it is not.