A medieval tower rising sixteen metres above a graveyard beside the sea, with a nineteenth-century Catholic church built directly into its fabric, is an unusual enough sight. What makes the ruins at Abbeyside stranger still is the layering: Augustinian friary, suppressed and repurposed, ruined within a century, and then partially absorbed by a modern building on the opposite shore of the Colligan estuary from Dungarvan, close enough that the castle there sits only about four hundred metres away across the water.

The abbey was founded around 1290 by Thomas Fitzmaurice Fitzgerald, and by the time of the Dissolution of the Monasteries in 1541 it had already been pressed into service as a parish church, which likely explains why the fabric survived as long as it did. It was in ruins by 1654. What remains today is the chancel and the crossing-tower, set within a graveyard defined by a masonry wall, with the sea forming the eastern boundary. The chancel retains a round-arched doorway in the north wall and traces of a triple sedilia in the south wall, a sedilia being a set of recessed stone seats used by officiating clergy during Mass. The four-storey tower is substantially complete, with a groin vault at ground level, remnant newel stairs at the first floor, and ogee-headed window openings at the belfry stage, their curved, pointed profiles a characteristic detail of late medieval Irish stonework. The modern St Augustine's RC church was built on the site of the north transept, incorporating the tower into its structure, so the medieval and the Victorian occupy the same footprint without quite merging. Architectural fragments surviving in the graveyard suggest the original complex included a cloister arcade, though little of that survives.

Look closely around the site and the details accumulate. Set into the ground at the chancel doorway is the graveslab of Donald McGrath, dated to the fifteenth century. An armorial plaque and a carved stone head have been set into the outer face of the west wall of the modern church, fragments that might easily be mistaken for decorative additions rather than salvaged medieval stonework. The putlog holes visible in the chancel walls are the voids left by the timber scaffolding poles used during original construction, a small reminder that this building was once new.