When test trenches were cut along a half-kilometre section of the proposed N11 Wicklow Bypass route, archaeologists uncovered not one but four distinct areas of ancient activity, clustered close together in a way that suggests this quiet patch of countryside was once a place of regular, repeated use.

The most substantial find was a burnt mound, a type of prehistoric feature found widely across Ireland and Britain, typically interpreted as the debris from a cooking or heating process involving fire-cracked stones. Stones would be heated in a fire, dropped into a water-filled trough to bring it to the boil, and then discarded in a growing heap once spent and shattered. The main mound at Ballyhenry measured roughly 25 metres long, 15 metres wide, and about a metre deep, making it a considerable accumulation. About 20 metres to the north of this lay a second spread of burnt mound material, some 7 metres across, and a third, smaller spread was found further north still, beside what may have been a shallow pit and a dump of apparently unburnt stone. A fourth area, towards the southern end of the test zone, was distinct in character: two parallel ditches with an area of burning between them and a large pit, suggesting a different kind of activity altogether. The findings were published in Bennett's 2003 excavation bulletin.