The site at Knockatober appears on the 1839 Ordnance Survey six-inch map, where cartographers noted it as a fort, though today only subtle traces remain visible to the trained eye. The rectangular enclosure measures approximately 65 metres from northeast to southwest and 55 metres from northwest to southeast, occupying a slight shelf on the south-facing slope of the hillside.

Within this larger boundary, archaeologists have identified traces of a smaller rectangular enclosure, roughly 40 metres square. The southeastern and southwestern edges still show evidence of the original defensive features; a wide, low earthen bank and the remnants of what was once a fosse, or defensive ditch. The remaining boundaries have been incorporated into more recent field fences, a common fate for many of Ireland's ancient monuments as they were absorbed into the agricultural landscape over centuries.

The site's documentation comes from the Archaeological Inventory of County Wexford, first published in 1996 by the Stationery Office in Dublin. Archaeological surveyor Michael Moore compiled and revised the entry in May 2012, incorporating findings from more recent research. While the fort's exact age and original purpose remain uncertain, its position in the landscape and defensive features suggest it once played a role in controlling or monitoring movement through this part of the Blackstairs foothills.