What makes this site at Lisgrew worth pausing over is the precision of its double-ringed design, a layered defensive arrangement that speaks to deliberate, considered construction rather than simple enclosure.

The fort measures roughly 30 metres across and is defined by an inner earthen bank, about a metre wide, separated from a larger outer bank, three metres wide, by a fosse on each side. A fosse, in this context, is simply a dug ditch, the excavated material typically piled up to form the bank beside it. The whole enclosure slopes gently downward toward the north, and interestingly, the outer fosse disappears on the north-eastern side, whether through erosion, later disturbance, or original design is not entirely clear. There are openings at the south-west and north, but the original entrance appears to have been on the east-south-east side, where both the inner and outer banks are broken by gaps of roughly 4.6 metres and 3.1 metres respectively, each with a causeway preserved across the corresponding ditch. That causewayed entrance, carefully oriented and structurally deliberate, is the detail that lingers: someone once chose this exact point on this ridge to pass through, and the ground still holds the memory of it.