 Evidence of settlements on Jura dating from the Mesolithic period was first uncovered by the English archaeologist John Mercer in the 1960s.There is a Neolithic chambered cairn at Poll a' Cheo in the southwest of the island.Jura is closer to Ireland's northern province of Ulster than it is to Glasgow, so it should not be unexpected that Irish people crossed the straits of Moyle and established the Gaelic kingdom of Dál Riata.