A vertical-wheeled water mill of this kind used the force of flowing water against a wheel mounted on a vertical axle to drive grinding machinery, a common enough mechanism in medieval and early modern Ireland, though relatively few urban examples survive in any legible form. What makes this one quietly remarkable is how long it has been traceable on paper, and how much of it appears to have survived underground.

The mill building appears on John Rocque's 1758 map of Kilkenny, which places it clearly in its urban context, and it is visible again on the first-edition Ordnance Survey six-inch map of 1839. Both records confirm it as a fixed feature of this part of the city across at least eight decades of cartographic documentation. When archaeologist Bernice Molloy carried out a test excavation in 2001, the dig revealed wall foundations built in limestone and red brick, along with an upstanding red brick wall that projected outward from the face of the medieval town wall itself. That the mill was constructed directly against the town wall, using it as one of its own structural boundaries, gives some sense of how tightly the industrial and defensive fabric of the medieval city was woven together. Much of the building's fabric is reported to remain preserved in situ beneath the surface, held in place by the very ground that buried it.