The enclosure does not appear on any Ordnance Survey historic maps, and there is nothing on the surface to suggest it exists at all. What gives it away is the grass itself: in dry conditions, the buried remains of an ancient fosse, a defensive ditch dug around the perimeter of an enclosed space, causes the crops or pasture above it to grow at a slightly different rate, producing a cropmark that only becomes legible from the air.

The monument came to light during the Bruff aerial photographic survey in 1986, when a flight over this part of County Limerick captured the outline as part of survey image AP 5/2053. What the photograph revealed was an oval form measuring roughly 40 metres north to south and 35 metres east to west, its shape defined by the line of the fosse beneath. A modern field boundary running north to south cuts directly across the eastern sector of the enclosure, a reminder of how agricultural reorganisation in later centuries could slice straight through earlier, unrecorded monuments without anyone knowing. The site sits on a gentle north-facing slope in improved pasture, just 20 metres northeast of the townland boundary with Kilballyowen, and within easy reach of a related field system recorded approximately 55 metres to the west and a second enclosure around 60 metres to the southeast. The cropmark has since been confirmed through ortho-imagery produced between 2005 and 2012 by Ordnance Survey Ireland, a Digital Globe image from 2011 to 2013, and a Google Earth image captured in September 2020.

Because the enclosure has no surface expression, there is little to see in the conventional sense on a visit to the area. The townland of Knockainy West lies in the Bruff district of County Limerick, a quietly agricultural stretch of the county where the landscape offers little obvious drama. The enclosure is on privately farmed land, so any visit would require the landowner's permission. Those with an interest in aerial archaeology, however, can compare the 1986 Bruff survey image against the more recent satellite orthoimagery to watch the oval form come and go depending on seasonal conditions. The fact that this feature remained completely unrecorded on historic maps until a single aerial survey flight in 1986 raises the obvious question of how many similar monuments remain undetected in the fields around it.