A cairn, in the broadest sense, is a mound of stones accumulated by human hands, and in an Irish prehistoric context these structures most often served as burial markers or territorial signals, raised during the Neolithic or Bronze Age by communities who shaped the land with considerable deliberate effort. This particular example at Killacorraun is recorded as a monument, which is itself a form of recognition, even if the details of its construction, dimensions, and condition remain largely unpublicised.

Very little specific information has been made publicly available about this site. What is known is that it holds a formal record as an archaeological monument in County Mayo, placing it within a county that contains an extraordinary density of prehistoric remains, from the field systems of Céide in the north to the megalithic tombs scattered across its boglands and hillsides. Mayo's bogland has historically acted as an inadvertent preservative, concealing and sometimes revealing structures that date back four or five thousand years. Without further documented detail about Killacorraun's cairn, its precise age, the circumstances of any excavation, and its current state of preservation remain open questions.