The term Iron Age refers to the period in a civilisation's development at which time iron working was the most sophisticated form of metalworking[?] achieved. The Iron Age is part of the Three-age system for prehistoric societies.
In
Britain, the Iron Age lasted from about the
5th century BC (although some believe it to have started significantly later, around
1st century BC) to the
4th century AD. Defensive structures dating from this time are often impressive (for example, the
brochs in
Scotland). This is possibly because of greater tension between better structured groups, although there are suggestions that in the latter phases of the Iron Age they existed simply to indicate wealth. Either way, during periods of
Roman occupation the evidence suggests the defensive structures served their purpose well. Many were re-used by later cultures, such as the
Picts, in the early
Medieval period.
Structures: