It is the kind of place that appears on heritage maps with a marker and a monument number, yet yields almost nothing when you press further, its details held in archive rather than published to the world.

Grenan itself is a townland in the south of the county, an area with deep medieval roots. The presence of a church site here is consistent with the broader pattern of early Christian and later medieval settlement across Kilkenny, where monastic foundations and parish churches were established from the sixth century onwards, many of them now reduced to a scatter of dressed stone or a graveyard outline in a field. Without more specific documentation currently available, the precise period of construction, the dedication, the extent of any surviving fabric, and the history of the site's use or abandonment remain unclear. What can be said is that the monument has been identified and recorded as part of the national archaeological inventory, which means someone, at some point, found enough there to warrant its inclusion.