These sites, known in Irish as cillíní (singular: cillín), were used for centuries to inter those who died without baptism, including stillborn infants and very young children. Because Catholic doctrine long held that the unbaptised could not enter heaven, they were excluded from churchyard burial, and so communities quietly established their own liminal spaces for them, often at field margins, on old monastic sites, or near ancient earthworks.

Cillíní are found across Ireland in their hundreds, and Clare has a considerable number. They were rarely marked with formal headstones, which is part of why they remain so obscure. The burials were typically carried out at night or at dawn, with little ceremony, and the grief was largely private. Over time, many of these sites became overgrown or were absorbed into farmland, their locations preserved only in local memory or in place-name traditions. The Catholic Church's position on limbo, the theological space assigned to the unbaptised dead, was formally reconsidered in 2007, but the cillíní themselves remain as quiet, physical records of a practice that shaped how generations of Irish families experienced loss.

The site at Rinneen has not yet been documented in sufficient detail to say much about its physical form, its extent, or the period during which it was in use. What can be said is that its existence in the archaeological record places it among a category of monuments that archaeologists and historians have only relatively recently begun to study with the seriousness they deserve.