Not through any dramatic collapse or deliberate clearance, but through the slow, incremental damage that comes when agricultural land and ancient earthworks occupy the same space without ceremony. The site is recorded as actively being destroyed, its bank broken in at least two places, and soil from those breaks dumped back inside the enclosure itself.

A rath, as this type of monument is classified, is an early medieval farmstead enclosure, typically dating from roughly 500 to 1000 AD, defined by one or more earthen banks and ditches that would once have surrounded a family's dwelling and outbuildings. The Farranbrien example is a fairly typical size: a circular area measuring approximately 35 metres across, enclosed by a bank that still rises about two metres above the exterior ground level on its intact sections, with a ditch nearly two metres deep running around the outside. The interior height of the bank, just 0.65 metres on the inside, suggests the ground level within the enclosure has been raised or disturbed over time. That disturbance is confirmed by recent digging that has left the interior badly uneven, sloping southward and cut through in ways that make any future archaeological reading of the site considerably more difficult.

What remains is a monument that communicates its own fragility more clearly than most. The sections of bank that survive to their original profile give a reasonable sense of how the enclosure once presented itself across the landscape, but the gaps to the south-south-east and west-north-west, filled in with displaced material, tell the more recent story just as plainly.