Many hilltop settlement sites show evidence of fortification, either banks and ditches running round the hill or stone walling. Sometimes there is a stone and timber combination, which, when set fire to, after battle, caused the partial melting and fusing together of the stones, resulting in a ‘vitrified’ wall.

From about the last 1000 years BC to the first few centuries AD, the nature of the archaeology you can see in Grampian changes: from burial and ritual monuments to settlement sites, which were protected originally by timber stockades, or the methods described above. Curiously, some of these defensive sites appear to be unfinished. Also dating from this time are other pieces of evidence of an agricultural society such as field systems, hut circles and souterrains, which were stone-lined underground passages, probably used as store-houses.

This category represents an especially interesting group, sometimes sited on coastal headlands, sometimes in places such as the Tap o'Noth or Dunnideer which require some exertion to reach the sites. (Make a day of it - take a picnic and stout footwear!) It’s a chance to take a good look at vitrified walls. How were they made? How much heat would be needed to melt stone?