That combination is not unusual in the Irish midlands and west, where the land holds an extraordinary density of earthworks, many of them so worn by centuries of agriculture and weather that only a slight rise in a field, or a curved line of scrub growth, hints at what lies underneath.

An enclosure of this kind would typically refer to a roughly circular area defined by an earthen bank, a fosse, or a combination of both, representing the remains of a settlement or farmstead from the early medieval period, roughly the fifth to the twelfth centuries. These sites are sometimes called ringforts, though the word fort is slightly misleading; most were homesteads, not military structures, built to enclose a household, protect livestock, and mark territory. The name Annaghcallow itself is worth pausing on. In Irish, "anach" generally refers to a marsh or boggy place, and the second element may derive from "caladh", meaning a landing place or ford. Together, they suggest a low-lying, waterlogged area beside a river crossing, exactly the kind of landscape where early farmers chose to settle on slightly elevated ground above the wet. That topographic logic, marsh nearby and a firm footing above it, governs the placement of hundreds of similar sites across the province of Connacht.