To a passing eye it reads as nothing more than a slight swell in a field, a faint interruption in the slope. To anyone who knows what to look for, it is the ghost of a rath, a ringfort, one of the most common yet persistently enigmatic monument types in the Irish landscape.

Ringforts, known variously as raths or lios depending on the region, were typically enclosed farmsteads of the early medieval period, roughly the fifth to twelfth centuries. A bank and ditch, sometimes doubled or tripled in more prestigious examples, defined a circular space within which a family and their animals would have lived. This one at Behagh has been levelled, its banks spread and flattened over centuries of agricultural use, until only the raised outline of the interior platform survives. That roughly circular area, detectable as a break in the gentle south-west facing slope, is all that remains above ground of what was once somebody's home and holding. Tens of thousands of ringforts survive across Ireland in various states of preservation; many thousands more have been reduced, like this one, to a trace in the topography.