Iron Age

The final period of prehistory is the Iron Age, which began around 500 BC and lasted into the early centuries of the first millennium AD. Iron superseded bronze as popular material for the manufacture of tools and weapons. The dates of the Iron Age vary considerably from one region to another.

The Iron Age began in Pembrokeshire with the arrival of groups of warlike Celts in about 500 BC. Their fortified settlements are scattered all over Pembrokeshire. Tall promontories that thrust out into the sea have defensive banks built across the neck to protect them from landward. The promontory fort on St. David's Head has the formidable Warriors' Dyke for its defence. The Deer Park is the largest promontory fort in Wales.

Inland there are many hill-top settlements enclosed by ramparts and among them three great hill-forts: Foel Drygarn, Carn Ingli and Garn Fawr, each with the visible remains of hut platforms and enclosures that provided refuge for women, children and stock in the event of enemy attack.

Traces of Iron Age fields are to be seen on the slopes above Porth Melgan and on Skomer Island, which has one of the best preserved ancient field systems in Wales. The Celts brought with them a new culture and a language that survives, in one of its derivative forms, as the Welsh language.