By the time anyone thought to measure it carefully, it was already half gone. When surveyors recorded the site in 1968, they found a D-shaped, slightly raised, stony and grass-covered area measuring roughly 21.5 metres north to south and 14.5 metres east to west, defined by a low scarp less than half a metre high. A field wall running roughly north-north-west to south-south-east had cut through the western side, and whatever lay beyond that wall had already vanished entirely.

The monument appears as an antiquity on the 1907 edition of the Ordnance Survey six-inch map, labelled simply as the site of a carn, which suggests that even by the early twentieth century it was understood to be a remnant rather than an intact structure. The name Carnroe itself preserves the memory of the feature, the Irish element "carn" pointing directly to the mound that once crowned the hill. By 1983, even the portion east of the field wall had been removed. What had been a landscape marker substantial enough to lend its name to the townland had, within the span of a few decades of recorded observation, disappeared almost entirely. The hill remains; the thing that named it does not.