The structure dates to around 1500 and marks the Inchiquin tomb, the burial place of Toirdelbach Ua Briain, founder of the Friary, and his descendants. What remains is unusual enough: a canopy with five groined vaults, the small ribbed ceiling compartments decorated with carved flowers and leaves, and a pediment above carrying an arcade of cusped ogee-headed panels, the ogee being that double-curved arch form associated with late medieval Gothic work in Ireland. The whole thing is still in its original position, which is rarer than it sounds for a monument of this age.

T. J. Westropp, writing in 1895, was not entirely kind about it. He described the design as "not of very happy design, the sides being quite plain," and noted the heavy horizontal mouldings running along a flat dovetailed arch, the small trefoil-headed recesses above, and a plain sloping roof, concluding that "the whole much resembles a fireplace." It is the kind of criticism that lodges in the mind. Westropp was not wrong, exactly; the monument lacks the dramatic sculptural ambition of some contemporaries, and the absent table leaves the canopy looking slightly purposeless, a frame without its subject. Yet the carved foliage tucked into the miniature groinings and the sides of the recesses rewards close attention, the detail concentrated in precisely the places a casual glance would skip over.