Easy to overlook and easy to misread, the depression runs roughly northeast to southwest and was noted in the late nineteenth century as a shallow rectangular ditch faced with stone, the kind of careful construction that signals deliberate engineering rather than a natural watercourse or field boundary.

The canal's existence was first recorded by Charles Smith, whose 1750 survey of County Cork made passing reference to it in admiring terms. Smith was a physician and antiquary who travelled extensively through Munster in the mid-eighteenth century, producing detailed accounts of the landscape, its settlements, and its infrastructure. By the time later observers came to look more closely at the feature, only the stone-faced ditch remained, the water and whatever purpose it once served having long since disappeared. Whether it was connected to the adjacent castle, to agriculture, or to some small-scale industrial use is not recorded. The canal sits in that category of minor historical features that were significant enough to be noticed and named in their own time, but not significant enough for their function to be carefully documented.