It was not a fort or a burial ground or any structure with a defensive purpose; it appears to have been purely ornamental, a deliberate piece of living geometry set into the landscape. By September 1982, when someone went to look for it, almost nothing remained. A few surviving trees, some scattered stones and rocks, and no discernible trace of whatever enclosing element had once defined the ring.

The circle is recorded on the Ordnance Survey 1:2500 plan surveyed between 1912 and 1916, which means it was still legible as a formal feature in the early twentieth century. It was most likely laid out as part of the designed landscape around Coole House, the Georgian country house on the same demesne. Coole House is perhaps best known today through its literary associations, but the wider demesne it sat within was shaped according to the conventions of estate landscaping, where ornamental plantings, structured woodland, and carefully placed features were used to give the grounds a composed, purposeful appearance. A tree-ring of this kind would have been one such feature, its geometry visible from certain vantage points, its combination of evergreen and deciduous planting chosen to give it year-round presence.

What makes the Coole tree-ring quietly curious is precisely how completely it has gone. The Ordnance Survey map caught it at a moment when it still had a legible form; by the time anyone recorded it on the ground, it had dissolved back into the pasture. The stones and rocks noted in 1982 may be the last physical remnant of whatever edging or enclosure once kept the planting defined.