By 1984, even that was gone, broken up during improvement works on the river, leaving only a documentary trace and the faint outline of an old laneway on an 1837 Ordnance Survey map to mark where generations of people once crossed.

The stone slab may well be the structure noted in 1682 by Sir Henry Piers of Tristernagh, a County Westmeath landowner and antiquarian whose observations were later published by Charles Vallancey in 1786. Piers wrote that at Knightswood "there sustainteth a late built footbridge", a phrase suggesting the crossing was relatively new at the time of his writing, though the use of a single flat stone as a bridge, sometimes called a clapper bridge, is a form with much older roots in Irish and British river crossings. The laneway that the 1837 map shows crossing the river at this point was not a modern road but an older route, and 350 metres to the north-east along that same roadway sits Rahanduff ringfort, an enclosed settlement of the early medieval period, the kind of circular earthwork that would have been home to a farming family or minor lord perhaps a thousand years before Piers made his notes. The proximity of the ringfort hints that this crossing may have served local movement for far longer than any single documentary reference can confirm.

The physical evidence is gone now, absorbed into the altered riverbank, but the Ordnance Survey linework and Piers's brief phrase preserve the outline of what was once a modest but functional piece of local infrastructure, the kind that rarely survives into the record at all.