Hillforts in Scotland Hillforts in Scotland are earthworks , sometimes with wooden or stone enclosures , built on higher ground , which usually include a significant settlement . They were introduced into Scotland during the Bronze Age from around 1000 BCE . The largest group are from the Iron Age , with over 1000 hillfort s , mostly below the Clyde - Forth line , most of which were abandoned during the period of Roman occupation of Britain . There are also large numbers of vitrified fort s , which have been subjected to fire , many of which may date to this period . After Roman occupation in the early Middle Ages some hillforts were reoccupied and petty kingdoms were often ruled from smaller nucleated forts using defensible natural features , as at Edinburgh and Dunbarton . Early studies . The first major study of Scottish hillforts was undertaken by General William Roy and published as " The Military Antiquities of the Romans in Britain " in 1793 . However , Roy only recorded forts like Burnswark with a close relationship to Roman constructions or which he wrongly attributed to be Roman in origin . George Chalmers ' ( 1742 – 1825 ) first volume of " Caledonia " ( 1807 ) contained an arbitrary list of forts , but recognised that defences at Burnswark were not just in anticipation of Roman invasion , but to defend against native threats . He also recognised some of the relationships between major and subordinate sites , and the importance of intervisiability between sites . The first serious field research was undertaken in the 1880s and 1890s by David Christison . Classification . A . H . A . Hogg identified four types of hillfort : contour forts , promontory fort s , cliff forts and ridge forts . Contour forts , where banks and ditches are moulded to the shape of the hill , are the dominant form in Scotland . Promontory forts , usually employing coastal features can also be found , such as the largest one in Scotland at the Mull of Galloway . Different types of defensive style occur throughout the Iron Age period , some of which may have been a response to Roman siege warfare . There are different combinations in the use of earth , stone or timber . Timber was frequently in - filled with stone or other materials . In continental Europe the timber is often arranged vertically , but in Scotland horizontal timbers were more common . Bronze Age . Bronze working developed in Scotland from about 2000 BCE . As elsewhere in Europe , it was in this period that hillforts were first introduced to Scotland . They varied in size and form . Some had timber palisades and others ditches and ramparts . These included the occupation of Eildon hill near Melrose in the Scottish Borders , from around 1000 BCE , which accommodated several hundred houses on a fortified hilltop . Traprain Law in East Lothian , had a 20 - acre enclosure , sectioned in two places west of the summit , made up of a coursed , stone wall with a rubble core . The function of these forts have been debated , with some stressing their military role and others their importance as symbolic centres of local society . Iron Age . There is evidence for about 1 , 000 Iron Age hillforts in Scotland , most located below the Clyde - Forth line . The majority are circular , with a single palisade around an enclosure . They appear to have been largely abandoned in the Roman period , but some seem to have been reoccupied after their departure . There are also numerous vitrified fort s , the walls of which have been subjected to fire , which may date to this period , but an accurate chronology has proven to be evasive . Extensive studies of such a fort at Finavon Hill near Forfar in Angus , suggests dates for the destruction of the site in either the last two centuries BCE , or the mid - first millennium CE . Early Medieval . For the period after the departure of the Romans there is evidence of a series of new forts , some of which became the centres of competing kingdoms . These were often smaller " nucleated " constructions compared with those from the Iron Age , sometimes utilising major geographical features , as at Edinburgh , which was probably the main fortification of the Brythonic kingdom of the Gododdin and Dunbarton rock , who gave its Brythonic name of Alt Clut to the kingdom that dominated the Strathclyde region in the post - Roman period . All the northern British peoples utilised different forms of fort and the determining factors in construction were local terrain , building materials , and politico - military needs . The first identifiable king of the Picts , Bridei mac Maelchon ( r . c . 550 - 84 ) had his base at the fort of Craig Phadrig near modern Inverness . The Gaelic overkingdom of Dál Riata was probably ruled from the fortress of Dunadd , now near Kilmartin in Argyll and Bute .