The Dame's Mills occupied a small island in the Poddle River, a waterway that once ran openly through this part of Dublin before being progressively culverted. The mills worked by damming the Poddle to generate sufficient flow, and it was this engineering feature that gave both the mills and the gate, Dam's Gate, their names. Today the street above carries buses and pedestrians with no indication that any of this ever happened.

The mills were already well established by the sixteenth century, when they appear in the Dublin Assembly Rolls with the kind of incidental detail that makes municipal records unexpectedly vivid. In 1559, the city's treasurer and masters of works were instructed to build a stone wall from the gate to the end of the mill island, specifically to stop dung being dumped in the town ditch there. By 1562, the lessee, a man named William Foster, was being given a civic grant of twenty shillings towards repairing the arches that carried the mill watercourse under the street pavement outside the gate, on condition that he build them properly in lime and stone at his own ongoing expense. The mills had previously belonged to St Mary's Abbey, the large Cistercian house on the north side of the Liffey, and passed out of monastic ownership at the Dissolution in the 1530s and 1540s. By 1609, a tenant named Jacob Newman held them from the city.

The junction of Dame Street and Crane Lane is easy enough to find, sitting just west of the City Hall and a short walk from the river. There is nothing to see at street level, and no plaque or marker records what lies below. Researcher H.B. Clarke, working from a 1978 map of Frankish medieval Dublin, pinpointed this location as the site of the mills, but the archaeology remains entirely sub-surface. The Poddle itself still flows beneath the city here, joining the Liffey near Wellington Quay, though it does so invisibly. Visiting on a quiet morning, when the traffic briefly eases, it is at least possible to stand above the approximate spot and consider that the sound of water and grinding stone once defined this corner of the town.