Though the structure is now reduced to a fragment of a low limestone vault, measuring just 4.5 metres wide and standing barely 1.9 metres high, this modest ruin represents the legacy of one of Gaelic Ireland’s most influential scholarly families. The castle once stood on lands belonging to Duffiagh O’Duiganane, who held 163 acres here according to the Down Survey of 1656;8, though much of his property was covered in timber rather than farmland.

The O’Duignan family weren’t typical landowners; they served as historians and ollamhs, essentially learned teachers, to the Mac Raghnall rulers of Conmaicne and other Gaelic noble families across north Connacht and north Leinster throughout the Middle Ages. Their influence extended far beyond their estates in Fenagh parish, where they held most of the land during the 17th century. These weren’t warriors or merchants, but custodians of knowledge, preserving genealogies, laws, and histories in an oral tradition that stretched back centuries.

Today, what remains of their castle sits in Corragoly townland, perched on a gentle rise in the undulating, low;lying landscape typical of this part of Leitrim. The surviving vault, constructed from mortared limestone, hints at what was likely once a more substantial fortified residence. While the Down Survey maps don’t specifically mention a castle at this location, the physical evidence suggests the O’Duignans maintained a defensive structure here, perhaps as much a statement of their status as a practical fortification in an often turbulent medieval Ireland.