Castletown, Castletown, Co. Offaly
In the townland of Castletown, County Offaly, the remnants of what may have been an O'Carroll castle tell a fascinating story of medieval defensive architecture.
Castletown, Castletown, Co. Offaly
Historical records from 1605 mention this site in an Inquisition post mortem of Mulrony McTeig O’Carroll, where it’s described in Latin as ‘de Castr’ Vill’ et Campis de Castleton Keneleage’. Today, only the bawn survives; a defensive wall that once enclosed a square courtyard protecting a castle building that has long since vanished.
The surviving sections of the bawn, primarily the south and east walls, reveal intriguing construction techniques that date back to the thirteenth century. Where the base batter has been robbed out, we can see that these walls were built atop an earthen bank that formed the inner core of the structure. The stone walls essentially encapsulated this mud or earth bank, a building method that mirrors other contemporary fortifications like Ballykilmurry castle nearby, as well as Shrule castle in County Mayo and Ballylusky in County Tipperary.
This construction technique offers valuable insights into how early medieval castle builders approached defensive architecture in Ireland. Rather than laying foundations directly on bedrock or prepared ground, they created earthen banks first, then built their stone walls around and over them. It’s a practical solution that provided both stability and additional height for defence, whilst making use of readily available materials. The site, documented by researcher Caimin O’Brien and uploaded to historical records in May 2011, stands as an important example of thirteenth century Irish castle construction methods.





