It sits roughly 145 metres east of the townland boundary with Snugborough and about 50 metres south of Glenefy House, and it is the kind of thing that cartographers once missed entirely. The Ordnance Survey's six-inch map, published in 1840, makes no mention of it at all.

By the time the same survey produced its more detailed 25-inch edition in 1897, the feature had finally been recorded, described as a raised, sub-circular earthwork approximately 45 metres across on its northwest to southeast axis and around 52 metres on its northeast to southwest axis. It is defined along much of its edge by a scarp, which is essentially a short, steep slope in the ground surface, running from the southeast around through the south, west, north, and northeast. Enclosures of this general type, roughly circular or oval earthworks bounded by a bank or scarp, are found throughout Ireland and were used across many centuries for a range of purposes, from settlement and farming to burial and ritual, though without excavation it is rarely possible to say which function any individual example served. What the Castlecreagh enclosure was built for, and by whom, remains unrecorded. The monument was compiled by Fiona Rooney and uploaded to the national record in October 2021.

The enclosure is not signposted and sits on private agricultural land, so any visit would depend on the goodwill of the landowner. For those who want to get a sense of what is there before travelling, the earthwork is clearly visible on Google Earth imagery taken between 2011 and 2013, where it reads as a distinctly oval raised area against the surrounding pasture. Aerial or satellite views tend to show this kind of monument more clearly than ground level does, since the scarp that defines its edge can be subtle underfoot. If you do visit in person, low winter light is generally the best condition for reading earthworks in a field, as the longer shadows pick out slight changes in ground level that would be invisible on a bright summer afternoon.