This is a rath, the Irish term for a ringfort, a type of enclosed farmstead built during the early medieval period, typically between the fifth and twelfth centuries. Ringforts were once scattered across Ireland in their tens of thousands, serving as the defended homesteads of farming families, and this one at Shanbally is a quiet, partially surviving example of that landscape.

The site was recorded on the Ordnance Survey six-inch map of 1842 as a hachured circular enclosure roughly forty metres in diameter. By the time the same area was mapped again in 1902, the north-western quadrant had already been removed, suggesting the enclosure was gradually being absorbed into agricultural use. A bank and its accompanying external fosse, a shallow ditch dug around the outside of the bank for added defence and drainage, are still visible beneath the overgrowth. Writing in 1918, a local commentator named O'Leary described it as a medium-sized circular lios, the Irish word for a ringfort's enclosing earthwork, covering approximately half an acre. One of the more unusual features is a souterrain associated with the site, positioned on the outside of the southern bank. Souterrains are underground stone-lined passages or chambers, often found in connection with ringforts, and thought to have served as places of refuge, cool storage, or concealment. Their placement here, outside rather than inside the bank, is a detail worth pausing over.