This unusual fortification consists of a polygonal enclosure, roughly 35 metres in diameter, surrounded by a mortared rubble wall that still bears the scars of its martial past in the form of visible musket loops. Within the southern sector of this bawn, the foundation walls of two possible house sites remain, with one potentially marking the location of a now-vanished castle that may have given the townland its name.

The defensive layout reveals sophisticated military planning typical of late medieval Irish fortifications. The main enclosure is surrounded by a substantial flat berm, approximately 12 metres wide, which in turn is protected by an impressive fosse; a deep defensive ditch measuring up to 6.7 metres across at its widest point, narrowing to 2.5 metres at the base. The original eastern entrance survives as a stone-lined causeway spanning this ditch, though modern road construction has unfortunately cut through the northern defences. The polygonal design bears striking similarities to the bawn at Ballinlough Tower house, suggesting a regional architectural preference or perhaps the work of the same builders.

Historical records add another layer to the site's story. The Down Survey of 1655-6 marks it as Caiseal Roan, confirming its significance in the mid-17th century landscape. Archaeological assessment suggests this may represent a medieval bawn with an associated tower house, possibly constructed atop an earlier earthwork, indicating centuries of continuous defensive use of this strategic position. While time and destruction have claimed much of the original structure, what remains offers a tangible connection to the complex layers of Irish fortification traditions, from early earthworks through to the age of gunpowder warfare.