The townland of Killeentierna, in County Kerry, contains one such earthwork, a rath, which is the Irish term for a roughly circular enclosure defined by one or more earthen banks and ditches. These structures were typically built during the early medieval period, roughly between the fifth and twelfth centuries, and served as the fortified farmsteads of farming families across all levels of society.

Raths were the basic unit of rural settlement for centuries, and Kerry contains a particularly dense concentration of them, owing in part to the county's relatively undisturbed pastoral landscape. The banks, often several metres high when well preserved, would originally have enclosed a timber or stone dwelling, outbuildings, and livestock pens. The surrounding ditch provided both a physical barrier and a clear statement of territorial ownership in a society where land and cattle were the primary measures of wealth. Killeentierna itself is a small rural townland, and the presence of a rath there is consistent with the pattern of early medieval agricultural settlement that once covered this part of Munster.