It is roughly conical, with a flattened top, and around its circumference runs what appears to be an original ledge, almost a shelf cut into the body of the earthwork, sitting up to 0.95 metres above the base. That kind of feature is unusual enough to stop you looking at it as simply a lump of earth that time has left behind.

The monument, known locally as the Moat of Nicholastown, was already being mapped as something worth naming by the mid-nineteenth century; it appears annotated on the 1838 edition of the Ordnance Survey six-inch map. When David McGuinness surveyed it in 2013, and published his description the following year, the picture that emerged was of a tumulus, a burial mound, that is broadly well preserved but not without its complications. The mound measures roughly 12.4 metres north to south and 13.5 metres east to west, rising up to 2 metres on its southern side. Erosion on the eastern face has exposed the soil beneath, confirming that the core is predominantly earthen. Around the western half, a scattering of boulders at the base appears to represent the remains of a kerb, the kind of stone edging commonly used to define and retain prehistoric mounds, though a wide and irregular berm of displaced material beyond that kerb, particularly pronounced on the west side at 3.7 metres, points to later human disturbance rather than natural settling. The summit itself is a small flat circle, three metres across, clear on most sides and sloping gently from south to north.