Most court tombs, a Neolithic monument type in which an open forecourt leads mourners or celebrants toward a roofed burial gallery, follow a fairly consistent pattern: one court, one gallery, one end of a long cairn given over to the dead. At Mautiagh, the builders did something more elaborate. The cairn stretches 38 metres east to west and carries not one but two chambered galleries, one at each end, each roughly 4 to 5 metres long and 1.8 metres wide. A single lateral chamber sits near the centre of the cairn, close to its southern edge. The whole structure rises about 1.5 metres above the surrounding plateau on a knoll of exposed limestone, giving it a presence that would have been legible across the Glenaniff valley below.

The arrangement of the courts is unusual in itself. At the western end there is a shallow orthostatic court, meaning one formed from upright stones set into the ground rather than built up in a more elaborate curved or horned configuration. At the eastern end, by contrast, there is a proper oval court, measuring 5 metres east to west and 4 metres north to south. This asymmetry, one informal and one more formally defined, is the kind of detail that keeps archaeologists attentive. Attached to the northern side of the cairn is a separate enclosure, the function of which is not recorded here but which suggests the monument was part of a wider complex of activity on this plateau. The site was documented in detail by Ruaidhrí de Valera and Seán Ó Nualláin in their 1972 Survey of the Megalithic Tombs of Ireland, which remains the foundational reference for monuments of this type across the country.