What makes Kilbonane quietly arresting is not the ruin itself but what lies to its south: a cluster of low, uninscribed stones, graves marked by nothing more than plain fieldstone, their occupants unrecorded and now unrecoverable. The enclosure, roughly 40 metres east to west and 35 metres north to south, is bounded by a stone-faced earthen bank, the kind of boundary that in Irish ecclesiastical sites often signals origins far older than any surviving masonry.

The ruined parish church of Kilbonane occupies the northern half of the enclosure. The graveyard around it has been in occasional use into relatively recent times, which gives the site an unusual layered quality, the very old and the merely historical sharing the same ground. The earliest legible headstone now on site carries a date of 1758, though a local researcher, Brunicardi, recorded in 1913 that a stone dated 1727 was present at that time, suggesting some markers have been lost or have become unreadable in the intervening century. The uninscribed stones to the south of the church are harder to date and may represent a much earlier stratum of burial practice, when carved inscription was either unavailable or simply not the custom.