The quay as it exists today is, in a real sense, built on centuries of deliberate land reclamation, each generation pushing the waterfront a little further out into the river until the original shoreline became a matter of archaeology rather than experience.

The earliest evidence for organised riverfront construction here dates to around 1305, when timber revetments, that is, frameworks of wooden planking used to hold back earth and stabilise a riverbank, were first put in place. Excavations at numbers 9 to 14 Arran Quay uncovered two front braced-timber revetments from this period, with a third also dating to the early 14th century. By the later 14th century these wooden structures had been replaced by stone walls, which extended the quay frontage further into the river and pushed the usable edge westwards. A subsequent stone wall, probably dating to the 16th century, may have extended the line still further. The excavations produced over 5,000 small finds, among them pottery, floor tiles, bronze pins, and objects of wood and leather, a material record of the traders and inhabitants who worked along this stretch of water across several centuries. The formal quay as a named civic feature came later: according to historian John de Courcy, it was created in 1682 by a William Ellis, running from Oldbridge to Mellows Bridge. It took its name from Richard Butler, Earl of Arran, son of the Duke of Ormond and his deputy in Ireland between 1682 and 1684.

Arran Quay runs along the north bank of the Liffey in the older part of the city, west of the Four Courts. The excavated area at numbers 9 to 14 is long since built over, and there is nothing to mark the site of the finds or the buried revetments below. What makes a visit worthwhile is the act of looking at the quay wall and the road surface and understanding that the ground underfoot is largely made ground, accumulated layer by layer from the medieval period onward, and that the river's original course lay somewhere beneath where people are now walking.