It is a cillín, the Irish term for an informal burial ground used for unbaptised infants, and its quiet, overgrown presence tells something of the religious and social anxieties that shaped rural Irish life well into the twentieth century. Catholic doctrine once held that unbaptised babies could not be buried in consecrated ground, and so communities created their own marginal spaces, often on boundary land, hilltops, or ancient earthworks, where these children could be laid to rest.

The site at Treanlaur appears on the Ordnance Survey six-inch map of 1838, annotated simply as "Graveyard", suggesting it had been in use, or at least was recognised, before the era of modern record-keeping. By the 1930 revision it is marked as "Children's Burial Ground (Disused)", though local information indicates that burials of unbaptised babies continued here through the 1930s, 1940s, and into the 1950s. The ground itself is a very slightly raised rectangular area, roughly ten metres by eight, enclosed on three sides by drystone field walls and open to the west, where a low scarp of around thirty to forty centimetres marks the edge. Small stones protrude from the interior, likely serving as grave markers, though they are now largely hidden beneath blackthorn scrub and long grass. The scrub and the modest, unmarked stones are characteristic of these sites across Ireland; the absence of inscribed headstones reflects both the informality of the burials and the grief that was often expected to be carried quietly, without ceremony or public acknowledgement.