This impressive structure, measuring roughly 50 yards across, was built with rough stone walls that originally reached 19 feet in height. The construction shows clever defensive design; the walls are 4 to 4.5 feet thick for the first 14 feet, then narrow to just 18 inches, creating a 2.5-foot-wide bench running along the interior that would have served as a fighting platform for defenders.

Within this protective enclosure, on the western side, archaeologists have identified the foundations of what was once a residence or castle. This rectangular structure measured approximately 30 by 21 feet, with substantial walls four feet thick; sturdy enough to withstand both the Irish weather and potential attacks. The combination of the outer defensive bawn and inner residence represents a typical fortified homestead of the late medieval or early modern period, when local landowners needed both comfortable living quarters and robust defences.

Historical records from an inquisition dated 18 March 1613-14 reveal that two men, likely members of the Fitzpatrick family, Edmond mac Shawn and Loughlin mac Donogh, held the surrounding townlands of Lisduff and Aghara. The site's ownership changed dramatically a few years later when King James I granted "Bawnagherry and Killoghery" to the Duke of Buckingham, reflecting the broader patterns of land transfer that occurred during the plantation period. Today, while much of the structure has deteriorated over the centuries, the visible foundations and remaining walls continue to tell the story of this once-formidable stronghold.