Marked in gothic lettering on the Ordnance Survey six-inch maps of both 1836 and 1908, this ringfort in Farranaglogh, County Meath carries the label "Cave Fort", a designation that points to something underground as much as above it. Set on a rise in an undulating landscape, the earthwork is circular and grass-covered, measuring roughly 48 metres across, and what catches the eye of anyone reading its contours carefully is a shallow depression inside the western perimeter. Running in an L-shaped arrangement, with an arm extending eastward and terminating in a circular hollow about 4.6 metres across, this feature is almost certainly the collapsed remnant of a souterrain, an underground passage or chamber of the kind commonly dug beneath early medieval ringforts in Ireland, typically used for cool storage or as a place of refuge. The name "Cave Fort" had already encoded this memory long before any archaeologist arrived to measure it.

The enclosure itself is a fairly substantial example of its type. Two concentric banks define the site, separated by a fosse, which is the formal term for the ditch dug between them, its depth varying from around 0.8 metres at the north-east to 1.7 metres at the south-west. The outer bank is best preserved along the western to northern arc and the eastern to south-western stretch, where it still stands to an external height of 2.1 metres at its most substantial point. Access was arranged through a ramp entrance and causeway on the eastern side, a deliberate piece of design that would have controlled movement in and out of the enclosure. The inner bank has been reduced in places to a scarp, a near-vertical erosion face, but enough survives to read the original form of the site without difficulty. Ringforts of this type, with their doubled defences, tend to be interpreted as the enclosed farmsteads of the early medieval period, roughly the fifth to twelfth centuries, though precise dating without excavation remains speculative.