The site at Knocknagapple sits on a summit, which was a deliberate choice in early Irish ecclesiastical tradition, placing the sacred at the highest point of the landscape rather than sheltering it in a valley. The graveyard itself is a narrow, roughly rectangular enclosure, about 30 metres north to south and 70 metres east to west, with the ruined church positioned towards its western end.

What makes the stonework here quietly interesting is the precision still legible in the fragments. Three jamb pieces and a coping stone survive, along with at least one block that may originally have served as a quoinstone, the cornerstone used to stabilise the angle of a masonry wall. The jamb fragments, which would once have formed the sides of a doorway or window opening, carry an external chamfer, a bevelled edge cut at roughly 45 degrees to soften the transition between two faces of stone. Two of the three also retain an internal rebate, a small step cut into the inner face that would have seated a door or shutter. The internal width of these openings was between 0.12 and 0.14 metres, and the chamfer itself runs approximately 0.1 metres wide. These are careful, deliberate measurements, the work of someone who knew what they were doing, even if the building they shaped has long since collapsed around them.