Two of the three earthwork enclosures recorded for the area have been located and studied; the third remains unaccounted for, its position known only from a mark on a map drawn three centuries ago.

The map in question is the Bateman survey of 1716 to 1717, which recorded the townland with three ringfort symbols, listed as entry number 58. A ringfort, or rath, is a roughly circular enclosure defined by one or more earthen banks and ditches, built during the early medieval period as a farmstead or place of enclosure for livestock. The two other ringforts in Knocknagapple have been identified on the ground, but the third, depicted towards the centre of the townland on Bateman's survey, has not. Whether it was levelled by later farming, obscured by vegetation, or simply marked in the wrong place by an eighteenth-century cartographer is unknown. The Bateman map predates the systematic surveys that would later document Irish landscapes in greater detail, and small discrepancies between early estate maps and physical reality are not uncommon. That makes this particular absence all the more interesting: there is documentary evidence for the site, but no confirmed earthwork to match it.