of dry stone. According to Malcolm Todd, "...'substantial houses' of the North may be over-represented in the archaeological record, by reason of their ability to more successfully survive as recognisable structures." The hillforts that stretched from the North York Moors to the Scottish Highlands are evidence of a distinctive character emerging in northern Great Britain from the Middle Iron Age onwards. They were much smaller than the hillforts further south, often less than 10,000 square metres in area (one hectare, about 2.47 acres), and there is no evidence that they were extensively occupied or defended by the Caledonians, who appear to generally have had a dispersed settlement pattern. By the time of the Roman invasion there had been a move towards less heavily fortified but better sheltered farmsteads surrounded by earthwork enclosures. Individual family groups likely inhabited these new fortified farmsteads, linked together with their neighbours through intermarriage. The reason for this change from hilltop fortresses to farms amongst the Caledonians and their neighbours is unknown. Barry Cunliffe considers that the importance of demonstrating an impressive residence became less significant by the second century because of falling competition for resources due to advances in food production or a population decline. Alternatively, finds of Roman material may mean that social display became more of a matter of personal adornment with imported exotica rather than building an impressive dwelling. Anne Robertson suggests that the Roman objects and materials (including relative finery and currency) found within many Caledonian structures indicates a trade network between the two cultures from as early as the first century AD, continuing until at least the fourth century AD. See also Antonine Wall Cruthin (In Ireland; possible descendants, predecessors or relatives of the Caledonians) Dicalydones The Mark of the Horse Lord References Bibliography Cunliffe, B, Iron Age Britain, Batsford, London, 2004, Frere, S, Britannia, Routledge, London, 1987, Moffat, Alistair (2005) Before Scotland: The Story of Scotland Before History. London. Thames & Hudson. Salway, P, Roman Britain, OUP, Oxford, 1986 Todd, M, Roman Britain, Fontana, London, 1985. External links The Scotsman - Mons Graupius, where the Romans defeated the Caledonii Famous Scots - Galgacus Historic UK - Romans in Scotland History Scotland Magazine Historical Celtic peoples Picts Former confederations Tribes of ancient Scotland Scotland in the Roman era