Built from roughly coursed limestone rubble with cut-stone quoins, the castle measures 13.8 metres by 10 metres and still retains its battlements, complete with well-preserved bartizans at the northeast and southwest corners. Historical records from the Civil Survey of 1654-6 describe it as “one castle in repair”, and various documents refer to it as the Black Castle of Burgesleagh in the barony of Eliogarty, taking its name from its position near the Black River.

What makes this tower house particularly fascinating is its elaborate defensive architecture, especially the ingenious entrance system. The original doorway, now obscured by a later stone outbuilding, sits a metre above ground level and leads into a complex entrance hall divided into three lobbies. Defenders could attack intruders through a cruciform loop directly facing the entrance, but the most remarkable feature was the ceiling; essentially a massive wooden trapdoor that served as an enormous murder hole, allowing defenders to rain down attacks from the chamber above. The interior preserves many original features across its floors, including window embrasures with flat-headed single lights, fireplaces with surviving corbels, and a garderobe chamber that runs along the east wall before doglegging south.

The third floor reveals the castle’s more comfortable side, featuring large window embrasures in each wall and an ornate cupboard on the east side of the north embrasure that cleverly concealed a small hiding hole beneath its now-missing base. Mural chambers and passages honeycomb the thick walls throughout the structure, accessed through various doorways that also lead to the battlements above. The castle sits amongst other historical features; a church and graveyard lie close by to the southeast, whilst a possible ringwork can be found to the east, suggesting this location has been of strategic importance for centuries.