Beneath a slight plateau near one of the headwaters of the Polehore Pill, the ground holds the ghost of an early ecclesiastical enclosure, the kind of large circular boundary, typically a ditch and bank, that once defined the sacred and administrative territory of an early Irish church site.

The evidence came to light during archaeological testing carried out in 2013, roughly 80 to 100 metres north of the parish church of Kilbrideglynn. Excavators uncovered the upper fill of a fosse, the term used for a substantial defensive or boundary ditch, measuring around 25 metres in width. That is a considerable feature. The fill was a uniform grey soil throughout, which, while unremarkable in itself, suggested the ditch had silted or been deliberately backfilled over a long period. Unfortunately it produced no datable material, so the age of the enclosure remains unknown. What the excavation did establish was the line of the fosse curving from the north-west to the north-east of the church. When that curve is read alongside the arc of the road running to the east and south of the same church, the two together would describe a roughly circular enclosure approximately 100 metres in diameter, centred on Kilbrideglynn church. Ecclesiastical enclosures of this kind are a well-recognised feature of early medieval Ireland, and their circular form is often preserved for centuries afterwards in field boundaries, roads, and property lines long after the original earthworks have been ploughed or built over. At Bregorteen, the road itself may unknowingly be following a boundary that predates it by a thousand years or more.