Megalithic tombs are large stone burial structures built during the Neolithic period, roughly five to six thousand years ago, and Mayo has an unusually dense concentration of them, particularly of the court tomb variety, where a roofless stone forecourt leads into a covered burial gallery.

The principal scholarly record for this site comes from Ruaidhrí de Valera and Seán Ó Nualláin, whose Survey of the Megalithic Tombs of Ireland, Volume II, covering County Mayo, was published by the Stationery Office in Dublin in 1964. De Valera and Ó Nualláin spent years systematically cataloguing the megalithic monuments of Ireland, and their Mayo volume remains a foundational reference for anyone trying to understand the distribution and classification of these structures across the county. Glenulra, like many of the sites they documented, sits in landscape that has changed enormously since the tombs were built, with blanket bog having spread across much of the terrain during the millennia that followed the Neolithic, in some cases burying or partially obscuring the stonework.