What little did survive long enough to be recorded was known locally not by any formal administrative name but as the Gripe of the Pig, a folk memory that attached an entire linear earthwork to the frantic digging of a widow's neighbours as they pursued a runaway pig through an underground passage all the way down to the Barrow.

The earthwork, more formally recorded as the Rathduff Trench, appears on an early seventeenth-century barony map of Idrone published by Gerard Mercator between 1606 and 1641, where it marks the north-western boundary of the Carlow barony at a time when that barony extended into what is now County Kilkenny. By 1839, when Ordnance Survey fieldworkers were compiling their detailed local letters, the trench was already nearly gone. John O'Donovan noted then that the earthwork carried traditions similar to those of the Black Pig's Dyke, a category of linear boundary earthwork found elsewhere in Ireland and generally associated with early medieval or prehistoric territorial division, and he recorded that it had been visible in living memory but that cultivation had largely erased it, save for a faint trace near Kellymount Hill. When a section in Shankill townland was excavated during the Cork to Dublin gas pipeline works in 1981 and 1982, archaeologists found the earthwork reduced to a low bank roughly 0.7 metres high, with a fosse, or ditch, beside it measuring just over a metre wide and a little more than a metre deep. Excavation showed why it was so diminished: the fosse had been recut in 1954 by the Land Commission as part of a drainage scheme, disturbing the original bank in the process. The original fosse had been considerably larger, five metres wide and nearly a metre deep.

The most legible trace of the Rathduff Trench today is said to be at Kellymount Hill on the south-eastern edge of the Castlecomer Plateau, where O'Donovan's 1839 observation that the gripe remained faintly traceable may still hold, though the landscape has had nearly two further centuries of cultivation since he wrote that.