During medieval times, this fortified structure was simply known as the Castle of Ballincuslane, lending its name to the surrounding parish. Once belonging to the FitzGeralds, one of Ireland’s most powerful Norman families, the castle served as both a defensive stronghold and comfortable residence in this corner of County Kerry.

Today’s ruins reveal the bones of what architectural historians call a T-plan castle, essentially a main rectangular block with a projecting wing. The main structure measures an impressive 20 metres by 12 metres, built with walls nearly 3 metres thick; a testament to the turbulent times when such fortifications were necessary. The projecting wing, which extends about 6.7 metres from the southeast side of the main block, contained the castle’s entrance and likely housed a now-vanished timber staircase that would have connected the various floors.

The castle’s internal layout tells us much about medieval life and social hierarchy. The ground floor, peppered with gunloops for defence, contained a kitchen with its fireplace at the northeast end. Moving upstairs, the second storey housed the main hall with a fireplace on the northwest side, whilst a private chamber occupied the northeast end, complete with its own fireplace and a latrine tucked into the east corner. The third floor continued this pattern of subdivided spaces, and the castle once boasted bartizans, those characteristic projecting turrets, at the south and west corners, with the western one positioned at wall-walk level where sentries would have kept watch over the surrounding countryside.