Now incorporated into the eastern end of farm buildings at Seatown House, this two-storey structure offers a glimpse into Ireland’s turbulent past. Built from coursed rubble masonry with carefully dressed corner stones, the castle measures 8.6 metres long and 6.8 metres wide, though only its lower courses remain original; the upper portions were added during the 19th century.

The interior reveals the defensive ingenuity typical of Irish tower houses. A round barrel vault spans the ground floor, still showing traces of its original wicker centring, whilst light filters through a pointed arched opening and a deep, square-headed window in the north wall. The most intriguing feature is the evidence of the castle’s original entrance in the west wall, where a murder hole in the corbelled roof of the lobby would have allowed defenders to attack unwelcome visitors from above. A spiral staircase, cleverly built within the thickness of the north wall, leads to the first floor, though both the stairs and roof have since been modernised.

Historical records from the Civil Survey of 1654-6 describe Seatown as “a small old castle with a hall adjoining, both thatched”, painting a picture of a working fortification that served both defensive and domestic purposes. Archaeological monitoring in 2005 during conversion works on an attached barn uncovered an assemblage of mid to late 18th-century pottery, providing a firm date for the house built against the castle’s western side. A glazed roof ridge tile found during the excavation may have come from either the castle itself or the now-vanished hall, adding another small piece to the puzzle of this enduring piece of Dublin’s medieval heritage.