The west belfry has since disappeared, but otherwise the Ordnance Survey account reads almost as a guide to what still stands: walls roughly five metres high, doorways facing each other across the nave from north to south, and windows that narrow dramatically from inside to out, some tapering to a slit of less than seven inches on the exterior face. That contrast between the generous interior splay and the tight exterior opening is characteristic of medieval stonework, designed to admit light while limiting exposure. The church sits on a low rise of ground, with the Killeenagarriff River running about twenty metres to the south, and a farmyard pressing close on the western side.

The place name itself carries a long documentary trail. Writing in 1904 and 1905, the antiquarian T. J. Westropp traced the parish designation back to 1201, when it appears as Kilmacconarva, shifting to Kilmaccongarub by 1302. A legal record from 1311 shows Johan, widow of J. de Burgo, claiming a messuage, lands, and woods here, which places the site within the sphere of Anglo-Norman landholding in Limerick. The scholar John O'Donovan rendered the name as Cillinnangarbh, but Westropp argued it commemorates a founder named Maccon Garbh. By the mid-seventeenth century, a map showed the building still roofed; in 1666, Killgarruffe and Clonkeen were granted to one S. Molyneux under the Act of Settlement. The church itself is dated to the fifteenth century, and the stonework bears that out: the south window retains a trefoil-headed light, a decorative form common in late medieval Irish ecclesiastical building, set in grit-stone on the interior face and limestone on the exterior.

The ruins form the northern boundary of a rectangular graveyard that remains in use, so the site is accessible in the way that many such churchyard ruins in rural Ireland are, without formal admission or infrastructure. The east gable had already collapsed before 1840, so visitors should not expect a complete shell, but the surviving north and south walls stand to their near-original height, and the blocked north doorway, its lintel a plain limestone flag, is clearly legible. The south doorway, pointed on the exterior and arched within, is constructed of cut limestone, though its western side showed damage even at the time of the 1840 survey. The river nearby and the working farmyard to the west mean this is a working rural setting rather than a managed heritage property, and the approach reflects that.