The giveaway is in the layout itself: a single main street running in a line, with a triangular marketplace once sitting at its western end. That triangular market space, a common enough feature of planned medieval towns where traders would gather and tolls would be collected, has long since been built over or worn away, but the linear form of the settlement remains largely legible if you know what you are looking at.

The borough was established by the Archbishops of Dublin as early as 1242, according to McNeill's research, placing its foundation firmly in the period of Anglo-Norman urban expansion across Leinster. The Archbishops of Dublin were significant landowners in this part of the county, and the creation of a borough, a formally chartered settlement with defined legal and commercial rights, would have served both administrative and economic purposes. By 1326, a surviving extent, a document recording the value and contents of an estate, lists sixty-six burgesses attached to the settlement. A burgess was a recognised inhabitant of a borough, typically holding land in exchange for rent and certain obligations, and sixty-six of them suggests a community of real commercial weight for the period, not simply a village but a functioning urban unit operating under ecclesiastical lordship.

Rathcoole sits on the N7 corridor, and arriving by road today gives little immediate sense of the medieval fabric beneath. The triangular marketplace at the western end of the main street is the feature worth looking for, or rather looking for traces of, since its outline may survive in the way property boundaries and road junctions converge rather than in any standing structure. The linear street plan is best appreciated on foot or on a large-scale map, where the single spine of the settlement becomes clear. Researchers and local historians working from the notes compiled by Geraldine Stout will find the McNeill references a useful starting point for understanding the documentary record behind what is, on the surface, a thoroughly ordinary suburban street.