At Boyhill in County Galway, a rath, the Irish term for a roughly circular earthen ringfort typically used as a farmstead enclosure during the early medieval period, survives in a condition that challenges even the idea of survival. Across much of its southern arc, from the south-east around through the south and on to the west, no surface trace of the defining bank remains at all. The monument is less a presence in the field than an absence, a gap where something once was.

What can be measured still tells us something. The rath is subcircular in plan and extends approximately 34 metres east to west, a modest but not unusual size for this class of monument. It sits in undulating pastureland, the kind of gently rolling ground that makes County Galway such fertile territory for early medieval settlement. More telling than its eroded bank, perhaps, is what the field system has done to it. Three separate field boundaries cut through the monument at its north-north-east, south, and west-north-west sides, and all three converge inside the enclosure, just to the east of its centre. The rath has not simply been worn down; it has been incorporated, divided, and reorganised by successive generations of farmers who either did not know what lay beneath their boundaries, or did not much mind.