A roughly circular embanked enclosure, somewhere between ten and fifteen metres across, was recorded on Ordnance Survey maps in both 1838 and 1922, but today the ground offers almost nothing to confirm it. A faint undulation on the south-western side may be all that remains of what was once a legible feature in the landscape.

Embanked enclosures of this general type are relatively common across Ireland, and many are thought to date from the early medieval period, roughly the fifth to twelfth centuries, when small ringfort-like structures served a range of agricultural and possibly defensive purposes. The earthen bank that defined such an enclosure would originally have been raised from material dug out of an interior or surrounding ditch, creating a low circular boundary. At Carrowcastle, the enclosure sat on a slight rise in the terrain, which was a characteristic choice of position, offering drainage and modest elevation. The fact that it appeared on two separate Ordnance Survey six-inch map editions, nearly a century apart, suggests it was still a recognisable feature well into the twentieth century, even if gradual ploughing, grazing, and the general settling of the soil have since reduced it to near-invisibility.