But underneath it, or rather before it, lay something older: an earthen rath enclosing the same ground. A rath is a roughly circular earthwork enclosure, common across Ireland, though usually associated with secular settlement rather than religious use. Here, the presence of one surrounding a burial site points toward a different function entirely, suggesting that this corner of Killiney may once have formed part of an early ecclesiastical enclosure.

The evidence for this earlier phase comes from the antiquarian William Frederick Wakeman, who noted in 1892 that the cemetery had originally been bounded by an earthen rath before the stone wall took its place. Wakeman was a careful observer of early Irish monuments, and his observation, though brief, carries weight. Earthen enclosures of this kind were a characteristic feature of early Christian monastic and church sites in Ireland, where a roughly circular boundary defined sacred ground and set it apart from the surrounding landscape. The replacement of such an enclosure with a later stone wall is a pattern seen at other sites around the country, and it tends to obscure rather than erase the earlier arrangement. The research notes compiled by Geraldine Stout and Padraig Clancy draw on Wakeman's original observation to flag the site as a possible ecclesiastical enclosure, though the full extent and date of any early religious foundation here remains uncertain.

The church sits on Marino Avenue West, reached by heading east off the Killiney Hill road. The setting is residential and unassuming, and there is no dramatic approach. What a visitor is really looking for is the form of the boundary itself, the curve of the enclosing wall, which may preserve the line of the original rath beneath later stonework. Reading a landscape like this takes a little patience and some willingness to look past the surface detail. The site is not managed as a heritage attraction, so expectations should be modest; this is a place that rewards quiet attention rather than obvious spectacle.