Located just 500 metres south-southwest of Castle Warren, this rectangular earthwork measures 48 metres from northeast to southwest and 29 metres from northwest to southeast. The site’s defensive features are still clearly visible: a low, wide earthen bank, roughly three metres wide and half a metre high on both sides, surrounds the interior space. Beyond this bank runs an external fosse, or defensive ditch, also three metres wide though only about 30 centimetres deep today after centuries of silting.

The original entrance to this fortified enclosure remains a mystery, though it likely stood somewhere in the northwest quadrant, now thoroughly obscured by dense vegetation. A modern field fence cuts through the monument, dividing it as it runs from northwest to southeast. Within the protected interior, archaeologists have identified traces of what appears to be a rectangular building, catalogued separately in the archaeological record.

This type of moated site was once common throughout medieval Ireland, particularly from the 13th to 15th centuries. They typically served as fortified homesteads for Anglo-Norman settlers or prosperous Irish families, offering protection in uncertain times whilst managing agricultural estates. The poorly drained soil that characterises this location would have made the defensive moat particularly effective, as the surrounding marshland would have naturally filled the fosse with water, creating an additional barrier against unwanted visitors.