That absence is itself a kind of curiosity. Ireland contains somewhere in the region of 45,000 to 50,000 ringforts, the circular earthwork enclosures built predominantly during the early medieval period, roughly between the fifth and twelfth centuries, that served as farmsteads for free farmers and minor lords. They are, in other words, extremely common. And yet even common things can slip through the cracks of documentation, and this particular rath, as the earthen variety is known, remains one whose details have not yet been made widely available.

A rath typically consists of one or more banks of earth and accompanying ditches enclosing a circular area, within which a household and its associated structures would have stood. The word Derrynacarragh itself is worth a moment's attention: the Irish doire, meaning an oak wood or grove, appears in the first element, suggesting that this part of Clare was once wooded ground, the kind of sheltered terrain that early medieval farming families often favoured when choosing where to build. Clare as a whole is rich in such monuments, many of them sitting quietly in fields, their low profiles easy to overlook from a road but unmistakable once you know what the gentle circular swell of an earthen bank actually means.