To understand a complex hillfort such as Castle Law, Forgandenny, where a sequence of overlapping defenses evolved over a long period of time, a range of methods is required. Detailed topographic survey was supplemented by geophysical survey and aerial photography to create a developmental sequence. The accuracy of this sequence was tested by excavation. Central to understanding the hillfort chronology is the set of nearly 90 radiocarbon dates from 10 sites. Excavations at Dunknock Dunning show that first enclosure dates to the Early Neolithic, the earliest known in Scotland. However the main period of hillfort construction spanned the late Bronze Age to late Iron Age, with a peak in the 7th – 5th centuries BC. Over time the forts became more complex as multiple ramparts were constructed on the most visible approaches. The final phase of hillfort activity dates to the Roman and post-Roman eras, when some of the earlier Iron Age sites were re-occupied, as in the case of Castle Craig broch.
Drone image by Kieran Baxter