Between the banks runs a fosse, the ditch that would have made the enclosure genuinely defensive or at least imposing, and the eastern entrance remains well-defined after more than a thousand years. A ringfort, or rath, was the typical settlement form of early medieval Ireland, a fortified farmstead enclosing a family's home, animals, and stores. This one overlooks poorly drained ground to the north, a deliberate choice that combined natural drainage advantages with a commanding view of the surrounding land.

What gives the site an additional layer of interest is the probable souterrain associated with it. A souterrain is an underground stone-lined passage, often branching, typically built beneath or adjacent to a ringfort to serve as a place of refuge, cold storage, or both. Their construction required considerable effort and planning, which suggests they were features of established, relatively prosperous farmsteads. The Grange monument has not escaped entirely unscathed: quarrying has eaten into it from the east through to the south-west, and where the original banks have been removed, an irregular scarp now forms the boundary in that sector. It is a reminder of how routinely these structures were treated as convenient sources of stone in the post-medieval period, and how much has been lost across the country by that incremental dismantling. That the twin banks and fosse survive as well as they do elsewhere on the circuit makes this example a relatively complete illustration of the type.