That absence is itself a curiosity. The site is defined by a low earth and gravel bank and an external fosse, which is a defensive ditch running around the outside of the bank, and together they enclose an area of roughly 47.6 metres north to south and 38.3 metres east to west. The bank is modest in scale, only about 3.5 metres wide and falling around a metre to the base of the fosse, which matches it in width. Dense vegetation now covers much of the site, softening what contours remain and making the whole thing easy to overlook even at close range.

The interior holds two structures. In the north-east quadrant sits a rectangular drystone building, its entrance marked by a lintel stone on the east side. A short distance to the south-west are the foundations of a subcircular structure, gapped at its north-west end, measuring roughly 5.2 by 4.2 metres internally. Drystone construction of this kind, built without mortar and relying on the careful placement of stones for stability, is common across early medieval and later Irish sites, though without excavation it is difficult to assign a firm date to these particular remains. On the western side of the enclosure, the bank and fosse are interrupted by a 13-metre gap, partially filled by a collapsed and overgrown stone wall that angles inward from the south-west. Whether this represents an original entrance, a later modification, or simple deterioration is unclear. Outside the enclosure to the east, an L-shaped stretch of walling built mainly from upright slabs is accompanied on its southern side by four low, stony, grass-grown mounds arranged in a rough square, which may indicate field clearance activity. Further north of that wall, a series of cultivation ridges survives, suggesting the island supported some form of agriculture at one point, modest in scale but deliberate in layout.

The site is drawn from the archaeological survey of the Iveragh Peninsula compiled by A. O'Sullivan and J. Sheehan and published by Cork University Press in 1996. Rabbit Island sits in Lough Currane near Waterville, and access requires a boat. The vegetation cover means that the earthworks are best appreciated by moving slowly around the perimeter, where the line of the fosse becomes legible underfoot even when it is not obvious to the eye.