The Down Survey maps of 1655-6, created as part of Cromwell’s massive land redistribution project, clearly mark a castle in what was then called Nashtowne. This 17th-century townland would later be split into two separate areas, Castlefield and Crowbally, with the castle falling within the boundaries of what became Castlefield.

By the time the Ordnance Survey cartographers arrived to map Ireland in 1839, the castle had vanished from the landscape. The structure appears to have been levelled sometime before the early 19th century, leaving no visible remains for the meticulous Victorian surveyors to record. The 1899-1900 revision of the maps confirms its complete absence, suggesting that whatever stood there had been thoroughly dismantled or absorbed into newer construction.

The story doesn’t end with the castle’s disappearance, however. Castlefield House, built in the early 18th century on or very near the original castle site, likely tells its own tale of architectural recycling. The house probably incorporates fabric from the medieval structure; a common practice when old fortifications gave way to more comfortable Georgian residences. These repurposed stones serve as silent witnesses to the townland’s transformation from a defensive stronghold to a domestic estate, embodying centuries of Irish history within their walls.