The hollow, roughly thirteen metres across at its widest and less than five metres deep from north to south, is ringed by a low bank of earth and stone, and within it a scattering of set stones mark graves with no particular order or symmetry. This is a cillín, a children's burial ground, of the kind found across Ireland wherever communities once laid to rest those who, for reasons of unbaptised status or other circumstance, could not be interred in consecrated ground.

What makes Ballygarraun particularly layered is that the site appears to occupy, or at least coincide with, a much older structure. The oval form and the slight hollow at its centre are consistent with a prehistoric barrow, a type of earthen burial mound used thousands of years before Christianity arrived in Ireland. Whether the community that began burying children here was aware of the earlier significance of the ground is not known, but the overlap is not unusual. Liminal places, sites already set apart from ordinary farmland, were sometimes repurposed across the centuries in ways that blur the boundary between prehistory and early modern practice. McCaffrey noted the site in 1952, and by then the bank and the scattered grave markers were already in fair condition, suggesting a degree of quiet, long-term survival rather than active maintenance.