The site offers commanding views down the valley to the southwest, a strategic advantage that would have been crucial for any medieval fortification. Though the castle itself has long since crumbled, its earthen bawn; a defensive wall typical of Irish fortified houses; still defines the boundaries of what was once a bustling settlement.

Archaeological surveys have revealed the foundations of several buildings clustered in the southern section of the bawn, running along the southeastern and southwestern interior walls. The most substantial of these is a roughly square structure that likely represents the main castle building itself, first documented on the 1839 Ordnance Survey map. A smaller building tucked into the western corner of the bawn may have served as an outbuilding or guardhouse, its modest foundations suggesting a more utilitarian purpose.

The site’s location in such poor, marshy ground might seem an odd choice for a castle, but the natural water supply and defensive advantages of the wetlands would have made it difficult for attackers to approach. Today, visitors to Castlewarren can still trace the outline of the earthen defences and imagine the medieval complex that once stood here, though wellies are strongly recommended for anyone venturing across the boggy approach.