A promontory fort of this type uses the sea itself as the principal barrier, with a stretch of clifftop land made effectively into an island by cutting one or more earthen banks and ditches across the narrow neck of land connecting it to the mainland. The result is a defended enclosure that required relatively little labour compared to what it achieved, and which could overlook the Atlantic approaches with considerable authority. Such forts are found at intervals around the Irish coastline, and most are thought to date broadly to the Iron Age, though some remained in use or were reoccupied much later.

Killard sits near the southern tip of the Burren coastline, where the limestone pavements of County Clare run out towards the mouth of the Shannon estuary. It is a landscape that has been settled and worked for thousands of years, and the presence of a coastal fortification here is consistent with the broader pattern of prehistoric and early historic occupation along this stretch of the Clare shore. Beyond the classification and location, detailed excavation records or historical documentation specific to this site are not currently available in the public domain, which means the questions that most naturally arise, who built it, when precisely, and what it was guarding against or controlling, remain open.