In a stretch of reclaimed pasture in County Limerick, a rectangular enclosure of roughly 30 metres by 25 metres exists not as an upstanding earthwork but as a cropmark, a faint outline readable only from the air, where buried features cause overlying crops or grass to grow at subtly different rates. The enclosure has never appeared on Ordnance Survey Ireland historic maps, which means it passed unrecorded for generations, an unremarkable patch of farmland to anyone walking across it.

The site came to light in 1986, when an aerial photographic survey centred on the Bruff area captured the distinctive rectangular shadow of a possible enclosure in the fields below. That survey image, catalogued as AP 5/2107, gave the first indication that something lay beneath the surface here. The monument sits roughly 155 metres west of the Morningstar River, which marks the townland boundary between Ballincolloo and Baggotstown West, and approximately 100 metres northwest of Ballincolloo House. A second earthwork, separately recorded, lies just 50 metres to the northeast, suggesting this corner of south County Limerick preserves a cluster of early enclosed sites. More recent satellite imagery, including Digital Globe orthoimages taken between 2011 and 2013 and images available on Google Earth, has confirmed the cropmark remains legible, though a post-1700 field boundary running north to south now bisects the rectangle, a later agricultural imposition laid across something much older.

Because the monument survives only as a cropmark, there is little to see on the ground without specialist knowledge or comparative images to hand. Cropmarks of this kind tend to be most pronounced during dry summers, when vegetation stress amplifies the differences between disturbed and undisturbed subsoil. The Google Earth orthoimages are a practical starting point for anyone wanting to orient themselves before visiting the area. The surrounding landscape is quiet agricultural country, and Ballincolloo House provides a useful landmark for finding the general vicinity. The site has been compiled in the Record of Monuments and Places under reference LI040-206----, and cross-referencing the neighbouring earthwork to the northeast adds useful context to any reading of the site.