What they are crossing, or skirting, is the remains of a ringfort, known in Irish as a rath, a type of enclosed farmstead that was the dominant form of rural settlement in Ireland from roughly the early medieval period through to around the twelfth century. Tens of thousands once existed across the country; many have been ploughed out, built over, or simply forgotten into the landscape.

This particular example is modest even by the standards of its type. The enclosure is roughly circular, measuring about 20.7 metres north to south and 23.2 metres east to west, and what survives is little more than a low earthen rise, at most 0.45 metres high, with a shallow external depression reaching a depth of around 0.4 metres running from the north-north-east to the west-north-west. In a freshly built rath, that depression would have been a more pronounced fosse, a ditch dug to throw up the bank and to define the boundary of the enclosed space within which a family, their livestock, and their outbuildings would have sheltered. Centuries of cultivation and weathering have softened everything down to what is now barely a rumple in the field.

The site sits in working pasture, and the earthworks are subtle enough that the time of year genuinely affects what can be seen. Low winter or early spring light, falling at an angle across the slope, tends to pick out slight changes in ground level far more clearly than midsummer sunshine. The shallow arc of the external depression, in particular, is the feature most likely to catch the eye when conditions are right.