Somewhere beneath the farmland near Calverstown in County Kildare, three circular features sit in a quiet east-to-west line, invisible from ground level and unremarked in any roadside signage. They exist, as far as current knowledge goes, only as cropmarks: faint differences in the colour and growth of crops above them, legible from the air but otherwise absorbed into the ordinary agricultural landscape.

Cropmarks form when buried features, walls, ditches, or pits affect how plants grow above them. Soil disturbed by ancient digging retains more moisture and produces lusher, taller crops, while buried stone foundations have the opposite effect. The three features at Calverstown appear to be barrows, circular burial or enclosure mounds each roughly sixteen metres in diameter. They were identified in an aerial photograph taken on 28 June 2018 via Google Earth, with the observation compiled by Caimin O'Brien from details provided by Pat Reid. Whether they are funerary monuments, stock enclosures, or something else entirely remains an open question; without ground investigation, the cropmark is suggestive rather than conclusive. What can be said is that their alignment along an east-west axis, and their grouping in a tight cluster of three, gives them a deliberate, organised character that sets them apart from random soil variation.