Historical records from 1574 show the castle belonged to one Donell Ecowga O’Flaherty, a member of the powerful O’Flaherty clan who dominated much of Connemara during the medieval period. Today, visitors to this windswept location can still trace the outline of the castle’s defensive bawn wall along the western riverbank, where sections of stonework survive up to two metres in height.

The rectangular bawn, which would have enclosed and protected the castle complex, appears to have had its main entrance on the eastern side. A raised mound in the southeast corner marks where the O’Flaherty castle itself once stood, though the tower house has long since collapsed into rubble. Archaeological surveys have identified foundations of additional buildings in the northwest corner of the enclosure; these were likely domestic structures, storehouses, or stables that supported daily life within the castle walls.

The site offers a glimpse into the turbulent history of Gaelic lordship in western Ireland, when families like the O’Flahertys controlled strategic coastal positions through networks of fortified strongholds. Though now reduced to fragments of masonry and earthworks, Bunowen Castle once commanded this stretch of Atlantic coastline, serving as both a defensive fortress and a symbol of O’Flaherty power in an era when control of land and sea routes meant survival in the contested landscapes of Connacht.