Running 21 metres long and standing 2.8 metres high on the north side of the road, this limestone rubble construction is peppered with put-log holes; telltale signs of its medieval origins. Whilst known locally as the ‘Cloister Wall’, archaeological evidence suggests it may have been part of a bawn wall, one of those defensive enclosures that once protected Irish castles and their inhabitants. Adding to the medieval mystery, a fragment of cut stone built into a modern wall behind a nearby bungalow appears to be part of a late medieval ogee-headed window, hinting at grander structures that once stood here.

Historical records paint a clearer picture of what this wall might have defended. The Down Survey maps from 1655-6 mark a castle in the townland of Johnstowne in this general area, and documentary evidence reveals fascinating connections to the medieval church. Before the Dissolution of the Monasteries, the Cistercian Abbey of Fermoy counted amongst its possessions a castle and 300 acres of land at Johnstowne. This valuable property passed through several hands after the abbey’s dissolution; it was leased around 1552 to one Humfrey Warren, before being granted in 1577 to Theobald Roche of Cregg.

Today, this weathered wall stands as one of the few tangible remnants of Johnstown’s medieval past, a fragment of what was likely once a much larger defensive complex. Whether it protected a castle, formed part of monastic buildings, or served both purposes over time remains open to interpretation, but its survival offers a rare glimpse into the fortified landscapes that once dominated rural Cork.