The one that sits on a gentle rise in Ballynacarrigy, County Westmeath, runs to approximately 75 metres at its widest, placing it well outside the ordinary range. That alone makes it worth a second look, even if what greets the eye today is modest: a fragmentary earth and stone bank worn down in most places to little more than a low scarp, interrupted by several gaps that opened up sometime after 1700. The interior rises slightly towards the centre, a subtle but characteristic feature of these enclosures, and the whole circular platform commands decent views across the surrounding grassland.

A ringfort, sometimes called a rath, is a type of enclosed farmstead built predominantly during the early medieval period, roughly between the fifth and twelfth centuries. They were the everyday domestic settlements of rural Ireland, typically defined by one or more earthen banks. This particular example sits on well-drained ground near a stream that marks the townland boundary with Conlanstown to the northwest, and within 250 metres of Rock Brook house to the south. On the first edition Ordnance Survey six-inch map of 1837, an old laneway is visible running northwest from Rock Brook towards the western side of the ringfort, suggesting the monument was still being navigated around, and perhaps still recognised as a feature of the landscape, well into the nineteenth century. A second ringfort lies roughly 240 metres to the south-southeast, which is not unusual in Westmeath, a county with a notably dense distribution of such sites. No original entrance feature has been identified at this one, and a field fence installed after 1700 cuts through the southern portion of the monument, further complicating what survives.