Carrowmore is not one monument but a whole cemetery of them, each tomb consisting at its most basic of a central dolmen, a large capstone balanced on uprights, surrounded by a kerb of boulders. The passage tomb tradition, which flourished in Ireland during the Neolithic period, roughly 4000 to 3200 BC, involved burying the dead in stone-lined chambers approached by a narrow entrance passage, often oriented toward a significant point on the solar calendar. At Carrowmore, this tradition takes a notably austere form: the tombs here tend to be smaller and structurally simpler than the great passage tombs of the Boyne Valley, yet in terms of sheer number and geographical coherence, the complex is extraordinary.

The principal survey of the complex was carried out by Seán Ó Nualláin, whose detailed work on County Sligo was published in 1989 as the fifth volume of the Survey of the Megalithic Tombs of Ireland. That study documented the surviving monuments at Carrowmore and provided the baseline record on which subsequent understanding of the site has depended. The monument covered here is a National Monument in State care, registered as No. 153, which places it under the legal protection of the Irish state. Carrowmore as a whole has been the subject of significant archaeological debate, particularly regarding the dating of individual tombs; excavations carried out in the 1970s and 1980s by a Swedish team produced radiocarbon dates suggesting some tombs here may be among the earliest megalithic structures in Ireland, though those findings have not gone uncontested among specialists.