The uncertainty is genuine: what survives is a low earthen bank, running roughly north to south for about seventeen metres before curving eastward at its southern end. It might mark the outline of a liss, the Irish term for a ringfort enclosure, typically a circular or oval area enclosed by one or more earthen banks and used as a defended farmstead during the early medieval period. Or it might simply be an old field boundary. The site appears on no Ordnance Survey map, which means it exists in a peculiar administrative limbo, known only through local memory and the work of archaeologists trying to reconcile what people remember with what the ground still shows.

What local information does record is that a liss at this location was removed in the 1940s. That kind of clearance was not unusual in mid-twentieth-century Ireland, when agricultural improvement schemes and changing farming practices led to the levelling of many earthworks that had stood since the early medieval period, roughly the fifth to twelfth centuries. Ringforts of this type were once among the most common monument types in the Irish landscape, numbering in the tens of thousands, but a significant proportion were cleared during the twentieth century. At Coarha Beg, whoever removed the liss left behind, perhaps inadvertently, this ambiguous curve of earth above the channel. Whether the bank is a remnant of the original enclosure or an entirely unrelated feature is a question the ground has not yet answered clearly.