It appears without fanfare, as so many such crossings do, but its presence on so significant a document gives it a quiet weight. The bridge has not been precisely located, and whether any trace of it survives above ground today remains an open question.

The map in question is the Down Survey, carried out between 1655 and 1656 under the direction of William Petty. It was among the most ambitious cartographic projects ever attempted in Ireland, commissioned by the Cromwellian administration to document landholdings across the country following the upheavals of the 1640s rebellion and the subsequent Cromwellian conquest. The surveyors recorded roads, rivers, townland boundaries, and features of practical use, including river crossings. A bridge appearing on such a survey would have been considered a notable landmark, something useful enough to warrant inclusion on a map whose primary purpose was to apportion confiscated land. Roebuck, in the barony of Rathdown in County Dublin, was within the broader hinterland of the city, and a crossing here would have served local movement between townlands and parishes in an area that remained largely agricultural well into the modern period.

Because the bridge has not been precisely located, there is no specific spot a visitor can be directed to with any confidence. What the Roebuck area does offer is the kind of quiet, semi-suburban landscape where earlier layers of settlement occasionally surface, in the form of field boundaries, watercourses, or the alignment of old laneways. The River Dodder and its tributaries thread through this part of south County Dublin, and the general line of older crossings sometimes persists in the layout of paths and roads long after the original structure has vanished or been replaced. Anyone with a particular interest in historical cartography might find it worth consulting the Down Survey maps directly, which have been digitised and are accessible online, to compare the recorded landscape of the 1650s with the terrain as it appears today.