While no visible traces remain above ground today, historical records suggest a castle once stood in this area, its stones and stories now completely vanished from the landscape. The site represents one of those intriguing gaps in Ireland's archaeological record, where documented history points to something substantial that has left barely a whisper of physical evidence behind.

Mountheaton House itself may hold the key to this puzzle. Built sometime after the original castle's disappearance, the house quite possibly sits directly atop the medieval structure's foundations. Some architectural historians believe fragments of the earlier castle were incorporated into the newer building, a common practice in Ireland where practical builders often recycled dressed stone and other materials from abandoned fortifications. Without extensive archaeological investigation, however, it's impossible to determine which parts of the current structure, if any, date back to the medieval period.

The proximity to Mount St Joseph monastery adds another layer of historical interest to the site. The Cistercians, who established their presence in Ireland during the 12th century, often built their monasteries near existing power structures, whether for protection, patronage, or strategic advantage. The relationship between the lost castle and the religious community remains unclear, but their close proximity suggests they were likely connected through the complex web of medieval Irish politics, land ownership, and religious patronage that characterised the region during the Middle Ages.