At a precise point on the River Suir where the tidal push of the sea gives way to freshwater, there once stood a fish weir that had been catching salmon for centuries before anyone thought to blow it up. The site, on the western edge of Coolnamuck Demesne in County Waterford, sits at the natural limit of the river's tidal range, the kind of location a medieval fisherman would have recognised immediately as productive ground. A fish weir is essentially a fixed barrier or series of barriers built across a river to trap fish as they move upstream; the Suir, historically one of Ireland's great salmon rivers, would have made this a commercially significant structure.

The weir may have a paper trail stretching back to 1415, when an extent, a formal administrative survey of lands and their value, drawn up for the nearby town of Carrick recorded six weirs or salmon pools in the area. Whether this particular structure was among them is uncertain, but its position and character make it a plausible candidate. By the time of the Civil Survey of 1654 to 1656, the weir was already described as broken, suggesting it had fallen into disrepair during the upheavals of the mid-seventeenth century. It survived in some form nonetheless, acquiring the Irish name Cor Uí Criotháin and the anglicised Davin's Weir, the latter after a leaseholder who held it in the early twentieth century. The end came in 1922, when someone attempted to blow it up. The attempt did not entirely succeed in that moment, but the weir was subsequently dismantled, leaving little trace of a structure that had once been productive enough to feature in the administrative records of two different centuries.