The site, which may incorporate elements of an earlier Anglo-Norman castle, tells a story of colonial ambition and defensive architecture. In 1621, as part of the plantation scheme for Longford and Ely O’Carroll, Robert O’Farroll was granted ‘the castle, village and lands of Bawne’, creating what became known as the manor of Bawne. The fortified house that likely followed this grant stands as a testament to the uncertain times of early 17th-century Ireland, when comfort and defence went hand in hand.

The original structure was cleverly designed as a compact fortress; a central rectangular block measuring roughly 10 by 7 metres, standing two storeys tall with defensive angle towers at opposite corners. Built from roughly coursed limestone rubble, only fragments remain today, including a section of the southwest wall featuring a large window with a distinctive hood-moulding typical of late 16th or early 17th-century craftsmanship. The southeastern tower, circular in plan with walls over a metre thick, bristles with at least five gun loops at ground level, whilst the square northwestern tower features similar defensive openings. Both towers were accessible from the main house through doorways at ground and first-floor levels, with the circular tower incorporating an ingenious stepped offset that supported a wooden spiral staircase.

Despite being marked as ‘Bawn Castle & Nunnery’ on historic Ordnance Survey maps, no evidence exists of any religious house at this location; the nunnery appears to be nothing more than cartographic folklore. A small stone bridge near the southeastern tower, likely contemporary with the house itself, hints at the site’s former grandeur. Today, these ivy-wrapped ruins offer tantalising glimpses of plantation-era Ireland, when new landowners built homes that were equal parts manor house and military outpost, forever watching for trouble across the Longford countryside.