Originally established by the O’More family, this abbey thrived as a religious centre until the suppression of monasteries in the sixteenth century. Following dissolution, the lands passed first to Sir Thomas Loftus and then to Richard Cosby in 1609, marking the beginning of a dramatic transformation that would see sacred buildings repurposed for secular defence.

The Cosby family, who fortified the abbey in the late sixteenth century, likely constructed a castle on the site during Queen Elizabeth I’s reign. Their most striking architectural intervention involved converting the fifteenth century church, located southeast of the tower, into a tower house. This remarkable transformation preserved one significant feature of the original church: a substantial arch, measuring 3.95 metres wide and possibly the original chancel arch, which now stands blocked up and incorporated into the castle’s eastern wall. The arch, crafted from punch-dressed chamfered limestone with diagonal tooling marks still visible, serves as a tangible link to the site’s ecclesiastical past.

Today, the ruins consist primarily of the eastern wall, stretching approximately 12.45 metres in length, with short remnants of the north and south walls still visible. The eastern wall reveals fascinating construction details, including large beam holes at first floor level and a doorway that once led to a chamber in the southeast corner. The partial north and south walls show evidence of narrow defensive openings known as slit opes, though these sections are now heavily deteriorated. Intriguingly, historical records mention a sheela-na-gig at the doorway, though this carved figure is no longer visible to modern visitors.