Local residents know it simply as the ‘old fort’, though its circular form and defensive features suggest it may be something rather more specific: a medieval ringwork castle. The site consists of a central raised platform encircled by a broad bank approximately 10 metres wide, with an outer defensive ditch, or fosse, bringing the total diameter to around 55 metres. These distinctive features are clearly visible from aerial photography, appearing as a perfectly circular, grass-covered fortification.

The site has captured local imagination for generations, spawning tales that blend history with folklore. According to Colin Byrne, a resident of nearby Briarleas, local tradition maintains that a tunnel runs from beneath the mound all the way to Herbertstown, though no archaeological evidence has yet confirmed this intriguing claim. Such stories are common around ancient fortifications across Ireland, often reflecting folk memories of sieges, escapes, or hidden treasures.

Ringwork castles like this possible example at Hollymount represent an important chapter in Ireland’s medieval history. Built primarily in the 12th and 13th centuries, often by Anglo-Norman settlers, these earthwork fortifications consisted of a raised circular or oval platform surrounded by a bank and ditch. Unlike the more famous motte-and-bailey castles with their distinctive conical mounds, ringworks provided a level surface suitable for timber buildings and offered a practical defensive position that could be constructed relatively quickly using local labour and materials.