The one at Knockaderreen in County Clare is a case in point: a rath, which is the earthen variety of ringfort, typically consisting of a circular area enclosed by one or more banks and ditches, built and occupied during the early medieval period, roughly between 500 and 1000 AD. These enclosures served as farmsteads for relatively prosperous farming families, the banks offering a degree of protection for livestock as much as for people.

Ringforts as a class are well understood. What varied enormously from site to site was the local circumstance: the status of the family who built it, whether the enclosure was later reused or modified, and how well the earthworks have survived centuries of agriculture and land clearance. Clare is a county with a notable density of such sites, its limestone landscape having preserved many features that elsewhere were ploughed flat. The place name Knockaderreen itself is worth a moment's attention. The "Knock" element derives from the Irish cnoc, meaning hill, and the remainder likely contains further Irish language roots, suggesting the site sat on or near a named prominence in the local terrain, which would have been a typical and practical choice for a rath builder looking to survey surrounding land.