A cist is a small stone-lined grave box, typically constructed from flat slabs arranged to form a chest-like chamber, and used throughout the Bronze Age in Ireland to inter the dead, often accompanied by pottery vessels or small personal objects. They are not grand monuments; they sit low in the ground, easy to overlook, and many have only come to light through agricultural disturbance or chance.

An Geata Mór, whose Irish name translates roughly as "the big gate", is a townland in Mayo, a county that contains an extraordinary density of prehistoric remains, from megalithic tombs to field systems buried beneath blanket bog. Cist burials in the region generally date to the Early to Middle Bronze Age, roughly 2500 to 1500 BC, a period when individual or small-group inhumation and cremation rites were replacing the communal tomb traditions of the Neolithic. Beyond the fact of its classification and location, detailed information about this particular cist, its dimensions, condition, or any finds associated with it, remains unavailable at present.