It arrived in 1907, transplanted from Leamaneh North, where it had once marked the entrance to a 17th-century fortified house, most likely set into a wall defining the courtyard in front of that building. What makes it quietly remarkable is the layered record it carries with it: a round arch with a stepped hood-moulding, two coats of arms carved into the stone, and beneath them an inscription in worn lettering that reads, 'This was built in the year of our Lord 1643 by Conor O'Brien and by Mary ni Mahon, wife of the said Connor.'

The two coats of arms tell a generational story. The first belongs to Conor O'Brien, dated 1643, the year the gateway was built. The second is that of his son, Sir Donat O'Brien, added around 1690, suggesting the structure was significant enough to the family to merit updating nearly half a century later. The O'Briens were a powerful Thomond dynasty, and Leamaneh, the fortified house from which this gateway was taken, reflects their position in Clare during a turbulent century that saw the Confederate Wars, the Cromwellian settlement, and the upheavals of the Williamite conflict. The inscription itself is unusual, not only for naming both husband and wife as builders, but for doing so in English at a time when such commemorative stonework more often used Latin. Mary ni Mahon, known from other historical sources as a formidable figure in the O'Brien story, is given equal billing here in stone. T.J. Westropp, the Clare antiquary, recorded the inscription in 1900, before the gateway made its journey to Dromoland.

The gateway now sits within the Dromoland estate, removed from the ruin it once served but intact enough that the inscription, though worn, remains legible. The stepped hood-moulding, a decorative projecting frame following the curve of the arch in a series of receding steps, is a detail typical of the grander architectural ambitions of 17th-century Irish tower house builders, and its survival in such condition makes the piece worth seeking out for anyone already on the grounds.