It was uncovered during drainage work around 1970, identified for what it was, and then reburied. That quiet fact says something about the place: a piece of medieval industrial infrastructure, hidden once by time and then deliberately hidden again, sits in ground that was once a tidal pond serving one of the more unusual types of mill in the medieval landscape.

A tidal mill worked by trapping seawater, or in this case tidal river water, behind a dam as the tide came in, then releasing it through a sluice to drive a wheel as the tide fell. The Dunbrody example sat at the junction of a small stream and the tidal reaches of the Campile, and its dam still survives as a causeway running roughly 180 metres to the northeast, connecting the mill site to the church and gatehouse of Dunbrody Abbey. Documentary evidence for the mill goes back to 1540, when it appeared as the "salt mill of Dunbrody" in records of the dissolved abbey's possessions, seized during the Henrician suppression of the monasteries. Sir Osborne Etchingham acquired the abbey's lands in 1545, and the mill passed through his family; his grandson John Itchingham still owned it at his death in 1616. By 1803 it was cartographically recorded on a manuscript map now held in the National Library of Ireland, suggesting it remained a functional or at least recognisable feature well into the nineteenth century.

The causeway, which once served as the mill dam, is the most tangible remnant visible today. Walking it, you are effectively standing on the structure that held back the tidal pond, with the abbey gatehouse rising at the far end where the ground begins to climb. The millhouse itself is gone, and the pond it once filled is long since reclaimed as agricultural land, but the line of the causeway gives a surprisingly clear sense of the mill's scale and its relationship to the monastic complex it once served.