Though no physical traces remain visible today, the site known locally as Tonacashlan (or Toinacashlan) sits near the historic abbey and continues to mark where this 16th-century fortification once stood. The castle’s existence is documented in historical records, notably mentioned by Neary in 1938, providing a tangible link to the turbulent period of late medieval Ireland when such defensive structures were essential for local lords and chieftains.

The area around Cong has long been significant in Irish history, with its famous abbey serving as a religious and political centre for centuries. The castle of Edmond would have been part of this broader landscape of power, likely serving as both a residence and defensive position during a time when control of land and resources in Connacht was hotly contested. Its location near the abbey suggests it may have played a role in protecting the religious site or controlling access to the important waterways between Lough Mask and Lough Corrib.

Archaeological surveys of the Ballinrobe district, including the comprehensive work compiled by D. Lavelle in 1994, have documented numerous historical sites around Lough Mask and Lough Carra, though Edmond’s castle remains elusive to the modern eye. The persistence of the place name Tonacashlan in local memory serves as an intangible monument to the castle, demonstrating how oral tradition can preserve historical knowledge even when physical structures have long since disappeared into the Mayo landscape.