These sites, known in Irish tradition as cillíní, were places set apart from consecrated churchyards, used over centuries to inter unbaptised infants and others considered ineligible for formal Christian burial. The one at Ballyourane is a raised, roughly rectangular platform measuring around fourteen and a half metres long by ten and a half metres wide, edged by a scarp no more than half a metre high. It is subtle enough that a person walking past might not register it at all, yet numerous grave markers survive across its surface.

The Ordnance Survey six-inch map of 1842 already records the site as a Children's Burial Ground, which tells us it was well established and locally recognised by the early nineteenth century at the latest. How much further back its use extends is difficult to say, though cillíní across Ireland range in date from the early medieval period through to the twentieth century, reflecting long continuities in folk practice and Catholic theology around the fate of unbaptised souls. The raised, defined outline of the Ballyourane example suggests the ground may have been deliberately demarcated rather than simply accumulated over time, a feature sometimes seen at sites with deeper roots.