A circular enclosure on a gentle west-facing slope in County Waterford, this ringfort presents a small puzzle at its western edge: a four-metre entrance gap, wide enough to walk through with ease, that has been deliberately blocked with drystone walling. Whoever constructed that barrier was, in effect, closing a door whose original counterpart nobody has yet located. The actual early medieval entrance, the one used by the people who built and inhabited this place, remains unidentified.

Ringforts, known in Irish as raths when built primarily from earthworks, were the most common form of rural settlement in early medieval Ireland, typically enclosing a farmstead or the residence of a local family of some standing. This example at Kilbryan is modest but well-defined: a roughly circular grass-covered area just over thirty metres across, bounded by an earth and stone bank between two and four metres wide and rising to around one and a half metres on its outer face. Stone facing survives on both the internal and external sides of the bank across much of its circuit, suggesting a degree of deliberate construction rather than simple heaped earth. A fosse, the shallow defensive ditch that typically ran around the outer edge of such an enclosure, is faintly traceable to the south and west, though little more than twenty centimetres deep now. A stretch of the bank along the northern and eastern arc has been planted with coniferous trees, which have altered the profile of the monument somewhat and distinguish it visually from the open grassland it otherwise occupies.