This ridge of elevated land to the south of the Liffey was the traditional eastern terminus of the Slighe Mhór ("Great Way") that cut Ireland in half in prehistoric times, running along the Esker Riada.

A community of farming and fishing Gaelic Irish people lived here by the 5th century AD, with a defensive fort in the vicinity of Cornmarket and High Street.

It is south of the Viking settlement site at Wood Quay and east of Dublin Castle; it was the main street in the medieval period.

Patrick FitzLeones, who was three times Mayor of Dublin in the late fifteenth century, bought a house on High Street in 1473.

[9] The street was excavated again in 1968–71; finds included post and wattle houses, leather shoes and boots, bone objects, metalwork, pottery, coins, animal bones, a Rome pilgrim badge from the early 13th century, a lead seal of Pope Innocent III, a spoon bit, and wood-turning waste.