What survives today is a fascinating architectural puzzle, with fragments of a 13th century castle woven into later medieval structures and 19th century additions. The site’s strategic position, overlooking an important river crossing, made it a natural choice for fortification; first as an ancient promontory fort, and later as the seat of Anglo-Norman power in this portion of North Cork.

The castle’s most prominent surviving feature is a circular tower at the southeast end of the main building range, standing about 6 metres high with thick walls that once housed narrow arrow slits typical of 13th century military architecture. Though much of the tower is now encased in later masonry and topped with Victorian battlements, glimpses of its medieval character peek through where the facing stones have fallen away. Stretching northward from this tower, sections of the original curtain wall survive in various states of preservation; some retain their medieval machicolations whilst others have been reduced to retaining walls for 19th century terraces. Perhaps most intriguing is what appears to be the remains of the castle’s great hall, its east wall still showing the internal arches of window embrasures and a garderobe tower with its central shaft intact.

This was Duncroth Castle, likely built by the fitz Hugh brothers who arrived in the late 12th century as part of the Anglo-Norman conquest of Ireland. Along with nearby Glanworth and Buttevant castles, it formed part of a network of strongholds controlling the Blackwater River valley and its tributaries. When the fitz Hugh line ended without male heirs, the castle passed through marriage to the powerful Roche family, who held it as their principal seat until the upheavals of the 17th century. Today, the castle stands as a testament to centuries of adaptation and reuse, its medieval bones still visible beneath layers of later renovations and romantic Victorian additions.