It belongs to a category of monument found widely across Ireland, typically a roughly circular area defined by an earthen bank, a stone wall, or a combination of both, enclosing a space that may have served as a farmstead, a place of assembly, or something more ceremonial. Without further detail, the precise form of this one remains an open question.

Knockanagh, like many Kerry townlands, lies in a part of the island where such enclosures are relatively dense on the ground, reflecting centuries of settled farming activity stretching back through the early medieval period and, in some cases, considerably further. An enclosure of this kind, sometimes called a ringfort or rath when defined by earthworks, or a cashel when built of unmortared stone, would typically have housed a farming family and their animals, with the enclosing bank or wall offering a degree of protection from both wildlife and neighbouring rivals. Kerry's terrain, particularly in its more upland and western reaches, preserves many such sites simply because later agricultural pressure was never intense enough to level them entirely.