At Ahacore in County Limerick, a ditch barrow, a type of funerary monument defined not by a raised mound but by a surrounding fosse or ditch, survives only as a faint circular trace in reclaimed grassland. The site measures approximately ten metres in diameter, and its outline becomes legible only when viewed from above, in aerial and satellite imagery where differences in soil moisture or vegetation growth betray the buried feature below.

The site was identified from Digital Globe orthophotography taken between 2011 and 2013, with the same circular form visible in earlier Ordnance Survey Ireland aerial images. A cropmark of a separate enclosure has also been recorded roughly fifteen metres to the west, suggesting this corner of Limerick may have seen sustained activity over a long period. Cropmarks appear when buried ditches or pits retain moisture differently from the surrounding soil, causing the grass or crops above them to grow at a slightly different rate, a difference that becomes readable from altitude even when nothing at ground level signals that anything lies beneath. The record was compiled by Caimin O'Brien and uploaded to the national monuments database in June 2020.

For anyone hoping to visit, the site lies in what is described as reclaimed grassland, meaning the landscape has been heavily modified by agricultural drainage and improvement over the centuries, which is partly why so little survives above ground. There is no monument to observe in the conventional sense, no earthwork to walk around or stone to examine. The value here is conceptual as much as physical: knowing that a burial monument of probable prehistoric date lies just below the surface of an ordinary-looking field, its presence confirmed only by satellite, is its own kind of quiet revelation. Those with access to Google Earth can examine the cropmark as it appeared in the orthoimage captured on 25 March 2017, which gives the clearest sense of what the archaeology actually looks like from above.