According to the Ordnance Survey Letters from 2002, locals still referred to a portion of a building as ‘Castle’, though by then little remained visible. The first edition Ordnance Survey map from 1838 captured what appears to have been the last substantial remnant; a rectangular structure measuring approximately 20 metres northwest to southeast and 12 metres wide, standing in a small clearing surrounded by woodland.

By the early 20th century, the castle had deteriorated significantly. Writing between 1909 and 1911, O’Murethi documented that only a single fragment of Rochford Castle remained at Castledillon, describing it as one ivy clad corner of the building with an external chimney projection that ran up the wall from a first floor fireplace. This evocative detail suggests the castle once held domestic quarters substantial enough to warrant proper heating, hinting at its former importance in the local landscape.

Today, no visible traces of the monument survive above ground. The site where the castle once stood now hosts a cattle pen and crush, with a farmyard and sheds immediately to the north. However, the castle’s story hasn’t entirely vanished. In 2001, archaeological monitoring of groundworks for a house about 70 metres northeast of the castle site uncovered medieval and post medieval pottery sherds in fill material that had been brought to level a natural hollow at some point in the past. Whilst archaeologist M. E. Byrne noted the tantalising possibility that this fill came from the castle site itself, such a connection remains unproven, leaving another thread of mystery in Castledillon’s medieval tale.