What remains is a rath, a type of ringfort that would once have formed the enclosed farmstead of an early medieval family, its interior defined by an earthen bank and, where that bank has degraded, by a natural scarp in the hillside. The site measures roughly forty metres north to south and thirty metres east to west, a subcircular shape that is fairly typical of the form, though the vegetation has done its work and the edges are now softened almost beyond recognition.

Ringforts are among the most common archaeological monuments in Ireland, with tens of thousands recorded across the country, yet individually they tend to receive little attention compared to more dramatic stone structures. They date broadly from the early medieval period, roughly the fifth to twelfth centuries, and functioned as enclosed settlements rather than military fortifications, the bank serving mainly to define a household boundary and manage livestock. What makes the Knockacarrigeen example quietly interesting is its context: it does not sit in isolation. An enclosure of a different kind lies immediately to its south, and a second ringfort stands approximately a hundred and twenty metres to the south-south-east. That clustering suggests this patch of North Galway was once a moderately busy corner of the early medieval landscape, with distinct but neighbouring settlements occupying the same gentle hillside within comfortable sight of one another.