Locals still call it "fort field", even though the ringfort it once contained was levelled around 1973, leaving nothing visible above ground. A rath, as these earthwork enclosures are generally known, was typically a circular bank-and-ditch structure used as a farmstead during the early medieval period; thousands survive across Ireland in varying states of preservation. This one does not survive at all, at least not in any form a passing eye could register.

What the place does retain is a kind of archaeological ghost. When the land is ploughed, dark earth comes up in a rough circle where the fort once stood. That blackening is characteristic of sites where organic material, settlement debris, and centuries of accumulated occupation have altered the soil in ways that persist long after the structure itself has gone. Before it was destroyed, the ringfort was recorded on the Ordnance Survey six-inch map of 1842 as a circular enclosure roughly thirty-five metres in diameter, which places it at the smaller end of the scale for such monuments but well within the normal range for a single-family farmstead of the early Christian period. Its removal in the early 1970s was not unusual for the era; many ringforts across Munster were cleared during agricultural intensification in that decade, their banks flattened and their ditches filled to make way for machinery.

There is nothing to see at Ballythomas in the conventional sense, but the site is a reasonable illustration of how landscape memory works in rural Ireland. The name holds when the earthwork does not, and the soil itself continues to mark the outline of something that was already more than a thousand years old when it was finally erased.