It is sub-circular in shape, measuring roughly 6.8 metres north to south and 9.3 metres east to west, and climbs to about a metre above the surrounding ground on its western side. No stone stands upright. The whole thing has the look of something deliberately forgotten, which, in a sense, it was.

This is a cillín, the Irish term for an informal burial ground used for unbaptised children, and occasionally others considered ineligible for consecrated ground under Catholic Church practice. Such sites are found across Ireland, often in liminal places: boggy margins, old field boundaries, the edges of townlands. The one at Coss sits in exactly that kind of in-between landscape, pressed up against a river in ground that resists easy cultivation. The stones that compose the mound are modest, averaging around thirty centimetres across and twenty centimetres thick, laid without ceremony and without markers. By the late nineteenth century the site had already fallen out of use, its purpose quietly concluded as attitudes and practices shifted.

What survives is not a graveyard in any conventional sense. There are no inscriptions, no headstones, no formal boundary wall. Just the accumulated weight of small stones in a wet field, arranged by people who had very few other options for the children they were burying.