What makes this particular enclosure at Ballytrasna worth attention is precisely how long it went unnoticed in any official record. Despite the long tradition of Ordnance Survey mapping in Ireland, this monument never made it onto the historic OS maps at all, remaining essentially invisible to cartographers for generations while the land around it was reclaimed for pasture.

The enclosure came to light through the Bruff aerial photographic survey of 1986, when imagery catalogued as Bruff 66 (AP 4/3681) revealed the outline of an oval earthwork in the northern corner of a field on a gentle west-northwest-facing slope in the foothills of Knockseefin. An enclosure, in this archaeological sense, typically refers to an area of ground defined by a bank, ditch, or raised earthwork, often of early medieval date in an Irish context, and used for settlement, agriculture, or ritual purposes. This one measures approximately 31 metres along its northwest-to-southeast axis and 25 metres across, placing it in a size range consistent with a small farmstead or ancillary agricultural enclosure. It sits 70 metres northwest of the townland boundary with Gortnanuv, with a spring rising just 10 metres to its northeast, the kind of proximity to water that is a recurring feature of early settlement sites in Ireland. Three further enclosures lie within 145 metres to the west and southwest, suggesting this was once part of a more extensive cluster of activity in the landscape. The record was compiled by Alison McQueen and Vera Rahilly and uploaded in July 2020.

The earthwork is on reclaimed pasture, so access would depend on landowner permission, and there is no formal public trail to the site. For those with an interest in aerial archaeology, the survey image Bruff 66 and Digital Globe orthophotos from 2011 to 2013, as well as a Google Earth orthoimage dated 25 March 2017, offer the clearest views of the monument's oval outline. On the ground, the feature is likely to read as a subtle raised bank rather than anything dramatic, and the nearby spring to the northeast, though small, is worth locating as a marker for orientation.