Though nothing remains visible today, this castle was once significant enough to merit detailed recording on the Down Survey map of Ballyloughloe parish, where it was annotated as "a castle in repaire". The 17th-century surveyors depicted it as a tower house with a two-storey dwelling attached to one side, standing at the heart of a protective bawn wall. The castle's strategic position wasn't chosen at random; about 100 metres to the northwest lies Tobernakill, a holy well that would have provided both practical water access and spiritual significance to the site's inhabitants.

The castle's recorded history offers a glimpse into the turbulent period of 17th-century Ireland. In 1641, the lands belonged to one Awly McGawley, listed in contemporary documents as an "Irish papist", a designation that carried significant political and social implications during this era of religious conflict. The castle appears to have survived in some form for nearly two centuries afterwards, as the 1837 Ordnance Survey map still showed a rectangular building enclosed within its bawn walls. This longevity suggests the site maintained some importance through changing political landscapes and ownership.

Today, the castle has vanished entirely from the landscape, levelled at some point after the 19th century. When archaeologists surveyed the site in 1973, they found no surface remains, and modern aerial photography confirms its complete disappearance. Yet the surrounding landscape still hints at the area's rich past; a settlement cluster lies about 160 metres to the south, suggesting this was once a thriving community centre. While Carn Castle itself may be gone, its story remains preserved in historical maps and documents, a reminder of the countless lost structures that once dotted the Irish countryside.