They are, in fact, tree-rings, ornamental planting features laid out by a landowner in the eighteenth or nineteenth century. What makes Broomfield quietly interesting is what those relatively recent earthworks were unknowingly built on top of: evidence of human activity stretching back thousands of years earlier, into the Bronze Age.

Excavation of one of the three circular-ditched enclosures revealed pits associated with Beaker activity. The Beakers were a widespread cultural grouping of the early Bronze Age, named after their distinctively shaped pottery vessels, whose presence has been identified at sites across Ireland and Britain from roughly 2500 BC onwards. The pits at Broomfield suggest some form of settlement or repeated occupation at this location long before the landscaping fashions of Georgian or Victorian estate management left their own, rather more visible, mark. The findings were documented by E. O'Brien, whose 1988 report on the site remains the primary published source. The entry in the record was compiled by Geraldine Stout and later updated by Christine Baker.

Broomfield is in County Dublin, though the site sits within a broader agricultural and suburban landscape rather than in any formally managed heritage setting. There is no dedicated visitor infrastructure here, and the enclosures themselves, being tree-rings rather than ancient monuments, are not marked or interpreted on the ground. Anyone with an interest in early prehistoric activity in the Dublin region would be better served by reading O'Brien's 1988 account before visiting, since the surface features alone give little indication of what lies beneath. The interest is largely in the layering, the way a landlord's ornamental planting scheme and a Bronze Age community's pits ended up occupying the same ground, one on top of the other, without either party being aware of the arrangement.