The landowner calls it "the fort field", and that quiet piece of inherited local knowledge turns out to be more accurate than the ground itself might suggest. What lies here is a rath, the Irish term for a ringfort, a type of enclosed farmstead built during the early medieval period, roughly between the fifth and twelfth centuries. At Ballyhar, the enclosure has been so heavily reduced over time that its circular form is now readable mainly as a low rise in the earth and an inward-sloping scarp, the remnant of what was once a substantial earthen bank surrounding a concave interior. The clearest trace of the original boundary survives along the north-eastern arc, where it runs alongside a field boundary and is still just perceptible as a slight swelling in the ground.

The site measures approximately twenty-eight metres across on its east-west axis, and the 1846 Ordnance Survey six-inch map records it as a circular enclosure of around twenty-five metres in diameter, suggesting the feature was already diminished by the mid-nineteenth century but still visible enough to be mapped. Around the same decade, the Ordnance Survey Name Books noted a rath on the north side of Ballyhar in the townland record for Kilcredane, which is almost certainly the same site. The name books were compiled as part of the wider Ordnance Survey project of the 1830s and 1840s, during which local placenames, antiquities, and topographical details were gathered from residents and clergy across Ireland, making them an invaluable, if occasionally imprecise, early source for sites like this one.