The site forms a distinctive wedge shape, measuring between 55 and 65 metres from northeast to southwest, and 61 metres from northwest to southeast. Though now overgrown and reclaimed by nature, the earthworks still clearly define the boundaries of what was once an important local stronghold.

The defensive features of this site remain remarkably visible despite centuries of abandonment. An earthen bank, approximately 5 to 6 metres wide and rising about half a metre from the interior ground level, encircles the entire area. Beyond this bank runs an external moat on all sides, measuring roughly 6.5 metres across with depths varying between 0.5 and 1 metre. These measurements, recorded by archaeologist T.B. Barry in his 1977 study of medieval moated sites in southeast Ireland, reveal the substantial effort required to construct such defences in medieval times.

Moated sites like Garnakill were typically built between the 13th and 14th centuries, often by Anglo-Norman settlers or prosperous Irish families seeking to protect their homes and agricultural holdings. The combination of earthen banks and water-filled moats provided both practical defence against raids and a visible symbol of status in the medieval landscape. Today, while the structures that once stood within these protective earthworks have long since disappeared, the surviving banks and ditches offer a tangible connection to Wexford’s medieval past, preserved in the very contours of the land itself.