An ecclesiastical enclosure is a roughly circular or oval boundary, often a raised bank or ditch, that early Christian communities used to demarcate sacred ground, and they are frequently the earliest evidence that a site was used for religious purposes at all. The trouble at Clogher is that no one can say with confidence whether those traces are genuinely man-made or simply the natural contour of the hillside itself.

The ambiguity is not unusual in Irish archaeology, where the landscape has been worked and reworked for centuries, and where a slight curve in a field boundary or a gentle swell in the ground can look, from altitude, exactly like an ancient enclosure. The photographs in question, taken from the Cambridge University Collection of Aerial Photography on 19 July 1967, capture the site at a particular angle of light and season that threw possible features into relief, but ground conditions and subsequent survey have not settled the question either way. The church and graveyard remain classified as related monuments, their origins and the full extent of any enclosure left open.