The Ordnance Survey's six-inch map of 1838 recorded it plainly enough, but by the time the surveyors returned for the 1922 edition, it had already disappeared from the record, levelled over the intervening decades by agricultural activity. What survives today is a low semicircular raised area, roughly 27 metres across at its widest, its eastern and south-western arc still faintly readable as a worn scarp dropping about 1.3 metres at its highest southern point. The western side has been cut through by a field fence, though a second fence along the northern edge appears to follow, or at least respect, the original curve of the earthwork.

The enclosure sits on a gentle rise, with the ground falling away to the south and south-west towards low-lying, damp terrain below. That positioning is typical of the kind of early enclosed settlements found across the Irish countryside. A rath, which is a type of circular earthen ringfort used as a farmstead enclosure during the early medieval period, lies just 30 metres to the north-west, and a further enclosure sits 45 metres to the east. The clustering of these features suggests this corner of County Mayo was once a more intensively occupied landscape than the quiet pasture it presents today, with the Carrowcastle enclosure forming part of a wider grouping rather than an isolated curiosity.