The rise is easy to miss, a low scarp describing a partial sweep from south-west to north-west, but it marks the outer edge of what was almost certainly a rath, the kind of circular earthen enclosure, typically ringed by a bank and ditch, that thousands of early medieval Irish farming families built to enclose a homestead and signal their presence on the land.

By the time the Ordnance Survey mapped this part of Mayo in 1838, the enclosure was still readable as a circular embanked feature, roughly 25 to 30 metres in diameter, its north-eastern edge already pressed against a field boundary. By the 1922 revision, the same feature was shown with hachuring, a cartographic convention indicating an earthwork, but a second field boundary had by then been driven through the western half of the interior on a north-west to south-east axis. Successive decades of agricultural activity did the rest. The enclosure has since been levelled, and the north-east to south-west field boundary that once abutted it has also disappeared. What survives is a single short length of the later fence line and, beside it, that remnant bank or scarp, the only physical echo of the original structure. A second rath, a separate and apparently better-preserved example, stands approximately 115 metres to the north, which suggests this part of the Carrowcastle landscape was once a place of some domestic density, two enclosed settlements within easy sight of one another, both now reduced to varying degrees of absence.