The castle met its end in a rather practical fashion; it was systematically demolished to provide building materials for the houses of nearby Cartron, close to Tubberscanavin. According to historical accounts from O’Rorke’s writings in 1889, the stone from the castle was carefully worked, being ‘tastefully hammered and chiselled’ before finding new life in the walls of local homes.

The castle itself appears to have been a modest structure, depicted on the Down Survey maps of 1655-6 as a single tower. These maps, created in the aftermath of the Cromwellian conquest of Ireland, provide one of the few visual records we have of the building’s existence. The Down Survey was a massive undertaking that mapped forfeited lands across Ireland, and its inclusion of MacDonagh castle suggests the site held some local significance during the mid-17th century.

Today, the site serves as a reminder of how Ireland’s built heritage has often been recycled through the centuries. The complete absence of visible remains speaks to the thoroughness with which the castle was dismantled, its stones scattered throughout the neighbourhood where they likely still form part of Cartron’s older buildings. This practical reuse of materials was common practice in rural Ireland, where good building stone was valued and rarely went to waste.