Somewhere within it, at Gleninsheen, there is a wedge tomb, a type of megalithic burial monument that takes its name from the characteristic shape of its gallery chamber, wider and taller at the entrance end and tapering inward, like a stone wedge driven into the earth. These structures date broadly to the late Neolithic and early Bronze Age, somewhere in the range of four to five thousand years ago, and the Burren contains a notable concentration of them, the local limestone lending itself to the massive slabs required for their construction.

Gleninsheen itself carries a name already loaded with archaeological significance. It is the find-spot of the Gleninsheen Gorget, one of the finest examples of prehistoric Irish goldwork ever recovered, a broad collar of sheet gold with terminals decorated in concentric circles, dating to around 800 to 700 BC and now held in the National Museum of Ireland. The gorget was found in a rock crevice in the area in 1932, and its discovery made Gleninsheen a place of some note in Irish prehistory. The wedge tomb represents an entirely separate layer of human activity at the same location, older by perhaps two millennia, documented in detail by Ruaidhrí de Valera and Seán Ó Nualláin in their 1961 survey of the megalithic tombs of County Clare, a volume that remains a foundational reference for the field.