What makes it particularly curious is the contradiction lodged in its own history: a local tradition knew it as Killeen Fort and understood it as circular, yet what actually survives on the ground is a square platform, roughly 32 metres across on its east-west axis, defined by a denuded scarp, meaning the bank or slope that once gave it definition has been worn down to the point where the boundary is more suggested than declared.

When James Neary recorded the site in 1914, he described a circular earthen fort of which only the outline remained, which suggests the feature was already in a poor state over a century ago. The gap between Neary's circular reading and the square platform visible today is worth pausing over. Enclosures of this kind, built up from earth rather than stone, were common across early medieval Ireland and served a range of purposes, from farmstead boundaries to more ceremonially significant enclosures. Over centuries, the original geometry of such earthworks can be obscured by ploughing, grazing, and gradual erosion, and a denuded scarp can make a square corner read as a curve, or vice versa. Whether the square form is original, or whether a circular enclosure has been reshaped by later land use, is not something the surviving evidence can settle on its own.

The name Killeen Fort is itself suggestive. Killeen, derived from the Irish cillín, most commonly refers to a small unconsecrated burial ground, often used historically for unbaptised infants or others excluded from formal church burial. Whether that name reflects an actual function of this site, or simply attached itself through local association over time, is unknown, but it adds a layer of meaning to what might otherwise seem like a featureless rise in the pasture.