Magh Adhair, Archaeological inauguration site near Quin, Ireland

Magh Adhair is an inauguration site and archaeological complex near Quin consisting of an irregular oval mound about 6 m high with a flat central platform reached by a bridging point on its western side, a surrounding fosse, a smaller stonier satellite cairn to the west, a bullaun stone with two water-filled depressions to the north, a 1.9 m standing stone called a ligaun, a fulacht fiadh and earthen enclosures, with the Hell river bordering the west.

Magh Adhair was the inauguration site of the kings of Thomond, notably the O'Briens, with ceremonies recorded in 1242, 1267, 1277 and 1311. In 981 Maelseachlainn plundered the Dal gCais and uprooted the Bile of Magh Adhair; in 1051 Hugh O'Conor felled the tree again. The mound was raised, according to the Lecan records, by Amhalghaidh Mac Fiachrach as his tomb and inauguration place.

The name Magh Adhair means "Adair's plain", after a Fir Bolg chieftain, son of Umor and brother of Aengus, from whom the mound reputedly took its name. Fairs called irachts were held around the mound into the 19th century; the last known fair took place in 1838, and gatherings may have continued until the Great Famine. The mound was also called Cregnakeeroge, from ciaróg, a beetle.

The location sits in open countryside northeast of Quin and is straightforward to visit on foot. The terrain is flat and accessible, making it easy to walk around and observe all the stones and mound features from different angles.

The mound is also called Cregnakeeroge, from the Irish word for a beetle, a name recorded alongside its better-known dedication to Adhair. About 500 m to the southwest stands Cahercalla, a tree-covered ringfort with three earthen banks, which has been linked to the inauguration rites. Clare holds 940 stone ringforts, 40 of them around Quin.