Measuring roughly thirty metres on each side, it was recorded on the Ordnance Survey six-inch map of 1842 with hachured markings, the small lines surveyors used to indicate an earthwork or raised boundary, suggesting it was already a feature of note rather than a working structure at the time of mapping. Today, the ground has been levelled, and what was once a defined enclosure has largely returned to ordinary farmland.

The site belongs to a category of enclosures found throughout Ireland, earthen or stone boundaries that may have served as farmsteads, ritual spaces, or early settlement sites, their origins often stretching back to the early medieval period or even earlier. What makes Fahanalooscane quietly worth noting is the precision with which its disappearance can be traced. By 1934, when the Ordnance Survey updated its six-inch mapping, a slight rise along the line of the western bank still survived, a last visible trace of the original boundary. At some point after that, even that remnant was lost to agricultural levelling. The enclosure is now known mainly through the gap it leaves between two moments of survey, present in 1842, reduced by 1934, and gone thereafter.