The castle occupies a dramatic clifftop position, with rocky shores below giving way to the small sandy beach of Trabaun about 200 metres to the north. From this vantage point, visitors can take in sweeping views northward to Kilcummin and south towards the town of Killala.

The castle’s defensive walls trace a distinctive D-shaped footprint, with the straight eastern edge formed naturally by the cliff face itself. The curved western side consists of a curtain wall that sweeps in a shallow arc from the southern cliff edge around to the northeast, though it stops about 8 metres short of completing the circuit. Time has not been kind to these fortifications; much of the wall has collapsed into grass-covered rubble banks, now standing roughly 2.7 metres high and overgrown with brambles. A small section near the southwest corner remains intact, showcasing the original construction of large, roughly hewn stone blocks with a characteristic base batter.

Two tower structures punctuate the defensive perimeter, though both are now largely ruined. At the southern end, close to the cliff edge, a rectangular tower measuring about 6.2 by 4.2 metres appears to have been added after the initial construction of the bawn wall. The northeastern terminus of the wall shows evidence of another possible tower, perhaps serving as a fortified gateway. Historical records remain frustratingly silent about Castlenageeha’s past, though local tradition maintains it was once a Burke stronghold. The castle appears on Ordnance Survey maps from 1838 and 1922, but today its grass-covered interior courtyard lies empty and featureless, with only a modern field wall marking the dangerous cliff edge.