The word "may" is doing real work here, because what remains of this site is, in the most literal sense, nothing at all.

The first edition Ordnance Survey six-inch map, surveyed around 1840, recorded a small, roughly squarish enclosure with rounded corners on this gentle slope, measuring approximately 32 metres northwest to southeast and 28 metres northeast to southwest. Enclosures of this kind are common across the Irish landscape and can represent everything from early medieval farmsteads to ceremonial or burial sites, their rounded or subcircular forms often the only visible clue to centuries of settled activity. By the time the second edition OS map was produced in 1906, the enclosure had been replaced on the cartographic record by a quarry. The quarrying almost certainly destroyed or severely damaged whatever earthwork or structural remains had survived to that point. The quarry was later filled in, and the house followed in the early 1970s, completing a sequence of interventions that left no trace visible at ground level.

What makes Rathronan worth noting is precisely this layering of erasure. The 1840 map catches the monument at what may have been its last recorded moment of legible existence; sixty-six years later it was already gone, replaced by an industry that consumed the very ground it occupied. The site now exists only as a mapped memory, a small squarish outline on a nineteenth-century survey sheet, with a modern dwelling sitting, unknowingly or not, where something considerably older once stood.