Two low walls, a scatter of tumbled stone, and an interior crowded with untended graves: it is the kind of ruin that asks more questions than the landscape around it can answer. Yet even in this reduced state, the place carries the weight of an active ecclesiastical life stretching back to at least the early fourteenth century, and possibly much further, given that the Irish name Cill Bhanbháin, meaning the church of Banbhán, points to an early Christian foundation.

The church appears in the papal taxation records of 1302 to 1307, where it is listed as Kilbannan within the Deanery of Ardfert, valued at six shillings and eightpence per annum, with tithes assessed at eightpence. These figures are modest, suggesting a small rural parish rather than a wealthy foundation, but the fact of its inclusion confirms that it was functioning as a recognised ecclesiastical unit within the diocese of Ardfert. By the time Ordnance Survey fieldworkers recorded the site in 1841, the building had already been reduced to its north and south walls. Their measurements give a useful sense of what once stood: the interior breadth was recorded at seventeen feet ten inches, the walls were two feet ten inches thick and still standing to a height of seven feet. A pointed doorway of cut limestone survived in the south wall, measuring four feet seven inches high and three feet two inches wide. That doorway, with its dressed stone and Gothic point, is the detail that anchors the ruin most firmly to the medieval period. By 2012, even this partial picture had deteriorated further, with much of the visible masonry collapsed and the interior largely obscured by loose stone and unmarked or overgrown burials.