The iron age The period known as the Iron Age lasted in Britain for about 800 years (from 750 BC to AD 43). The changes and technological innovations that occurred during this time were every bit as evolutionary as those that have occurred in the last 800 years, from the 13th century to the present day. A hillfort or hill fort is a type of earthworks used as a fortified refuge or defended settlement, located to exploit a rise in elevation for defensive advantage. They are typically European and of the Bronze and Iron Ages. Some were used in the post-Roman period. By Asiya 3KH The Iron Age was a prehistoric, archaeological era that existed from around 1200 BC to 100 BC (the 12th to 1st Centuries Before Christ). During the Iron Age, iron material was commonly used to make tools, so the era was named after it.