British history XII

Iron Age

Defence developments 450 BC

From 450 BC, hillforts continued to develop. Extra ramparts and ditches surrounded them and entrances were further fortified. Forts were also built on cliffs and promontories, and often became the centres for sea-borne trade. A particularly noteworthy site is at Hengistbury Head in Dorset.

http://www.bbc.co.uk/history/timelines/britain/iron_defence.shtml