Lying on the grass to the south of St. John's Church of Ireland building in Kill, Co. Kildare, is a chamfered stone mullion, a carved fragment from a window of a medieval church that no longer stands above ground. It sits there quietly, in the open, the kind of thing a visitor might step over without quite registering what it is. A second fragment, this one from a traceried window, was noted in 2002 but its whereabouts within the graveyard were not recorded, which means it may still be there somewhere, unnoticed or misidentified.

The 19th-century Church of Ireland building that now anchors the northern boundary of the rectangular graveyard, roughly 39 metres north to south and 55 metres east to west, almost certainly occupies the footprint of an earlier medieval church. The evidence is not only in the loose stonework on the ground. A late medieval font survives just to the north of the west doorway into the current church, the kind of wide stone basin used for baptismal rites, retained on site even as the building around it was replaced and rebuilt. The graveyard is enclosed by a stone wall dating to after 1700, with an entrance gate at the northwest corner opening onto the public road. Memorials within go back to the late 17th century. About 277 metres to the south-southeast lies Kill Moat, a raised earthwork feature that speaks to the same layered medieval presence in this part of Kildare. The place-name Kill itself derives from the Irish cill, meaning church or monastic cell, suggesting that organised Christian activity here predates even the medieval stonework by several centuries.