A journey to some of the mysteries of how the early Celts emerged and expanded since the 8th Century BC: from the collapse of the Hallstatt salt mines, to the bizarre rituals inside Bull Rock cave.

After thriving as traders for over three centuries, the Celts reinvented themselves as fearless warriors who waged war all over Europe.

In the 2nd Century BC, Celtic tribes established prosperous cities dedicated to trade along the Amber Road and the Danube; but external threats to their society forced them into smaller fortified settlements known as oppida.