It has been labelled a stone circle on maps since at least 1897, and that label has stuck despite growing archaeological doubt about what it actually represents. The name carries a certain romance, conjuring prehistoric ritual and ceremony, but the reality may be considerably more domestic.

The site first appears cartographically on the Ordnance Survey 25-inch edition of 1897, recorded with an external diameter of approximately 40 metres east to west, though even then the north-east quadrant was missing from the depiction. It does not appear at all on the earlier 1840 six-inch OSi map, which raises questions about how well it was understood in that period or whether it was simply overlooked. The monument sits 80 metres east of the townland boundary with Loughgur, placing it firmly within a dense cluster of related monuments: two conjoined stone circles lie 250 metres to the north, another stone circle 320 metres to the south-west alongside a later field system, and Caheer Baelee just 100 metres to the south-east. That density matters, because excavations on the nearby Knockadoon Peninsula at Lough Gur have reshaped how archaeologists interpret these features. Work published by Cleary in 2018 concluded that similar so-called stone circles in the area were actually Late Bronze Age settlement enclosures, the stone rings forming the boundaries of domestic houses rather than ceremonial spaces. The monument on Knockderc is considered unlikely to be a Bronze Age ceremonial circle for the same reasons.

Reaching the site today requires navigating rocky scrub woodland, and aerial photographs taken in September 2002 and Google Earth imagery from 2017 to 2020 tell a consistent story of progressive overgrowth. By 2018 the woodland had closed in enough that the circular form was difficult to distinguish at ground level. The western-facing slope does offer clear views to the west when the canopy allows, which gives some sense of how the landscape would have read to whoever built and used this enclosure. Anyone visiting should expect rough going underfoot and limited visibility within the monument itself; the clearest impression of its shape comes not from standing inside it but from looking at it from above.