Somewhere beneath a worked tillage field near Loughlinstown in Co. Kildare, a circular enclosure lies almost entirely out of sight. It does not survive as earthwork or stonework; it exists, at present, only as a cropmark, the kind of subtle discolouration in growing or ripening crops that reveals buried features to anyone looking down from above at the right moment. These marks appear because a filled-in ditch retains moisture and nutrients differently from the surrounding soil, causing the plants directly above it to grow slightly taller or greener, or to ripen at a different rate. The result, invisible at ground level, becomes legible from altitude.

The enclosure was reported by Jean-Charles Caillere and is visible on black and white aerial photography from 1995, as well as more recent satellite imagery from 2018. What the images show is a roughly circular form, approximately 55 metres across on its north to south axis, defined by the cropmark of a wide fosse, the term used for a ditch forming part of an enclosure boundary, running somewhere between three and four metres in width. The circuit is not complete; the fosse appears truncated along the northeast to south arc, with the traceable portion running from south through west to northeast. There are also faint indications of a second, narrower outer fosse running parallel to the first, visible at the southwest, set approximately five metres outside the inner one. A high tension electricity cable pole now stands within the northeast sector of the enclosure, a blunt reminder of how infrastructure cuts across landscape archaeology with little ceremony. Circular enclosures of this kind are a common feature of the Irish countryside; they range in date and function from prehistoric settlements to early medieval ringforts, and without excavation it is rarely possible to say which category a given example belongs to.