A rath, as these earthwork enclosures are commonly known, was typically a circular bank and ditch surrounding a farmstead or settlement, constructed and occupied throughout much of the first millennium AD. At Ballynaguila, even that modest description asks a little imagination of the visitor, because the monument has been largely levelled and the field boundary that once clipped its southern edge has since been removed.

When Denis Power compiled the record, uploaded in August 2011, the site could be cross-referenced against the 1923 Ordnance Survey six-inch map, which showed the enclosure clearly as a circular embanked feature approximately thirty metres in diameter, its southern arc already interrupted by an east-west field boundary that had been drawn across it at some earlier point. That boundary is now gone, but so too is most of the bank it accompanied. What the survey found was an arc of scarped edge, running from the south-west around to the north-west, following the original line of the enclosing element. It stands just 0.3 metres high and measures 3.4 metres in width, the kind of feature that registers more as a slight resistance underfoot than as anything visually commanding. The interior, under pasture throughout, slopes gently down toward the west.

The site sits on a west-facing slope in what is now agricultural land, and the surrounding pasture gives little away. To read the ground here requires patience and a reasonable familiarity with how earthworks survive, or rather how they tend not to. The surviving arc is most legible between the south-west and north-west quadrants, where the scarp retains some definition. Coming in low-angled morning or winter light, when shadows pool along even shallow earthworks, will help considerably. There are no formal facilities or signage associated with the site, and access would require local enquiry.