[8] O’Neill was able to define the earliest phase of the hillfort as smaller enclosure measuring 170 m by 80 m (1.2 hectares), with a gateway to the south, and defended with two rows of timber palisades.

The next phase was to greatly enlarge the hillfort, with timber laced ramparts, which took in much of the slope of the hill to the north-west, towards the river Severn.

The defences of the larger hillfort appear to have fallen into decay, and at some point, possibly at the time of the Roman conquest of Britain, were refurbished with a simple earthen bank.

There is the possibility that the earlier smaller enclosure dates from the Later Bronze Age and was contemporary with the earliest phase of the Breidden Hill fort near Welshpool.

These include smaller hillforts at Goron Ddu, Coed y Wig, Cefn Llan and Fronfraith in Llandyssil and Giant's Bank in Llanmerewig[12]