The Celts have left a lasting mark on the cultural traditions of Wales.
The migration from central Europe began in around 1,000 BC.
Evidence of the Celts' movements is found, partly through studying linguistic patterns.
Explore the celebrated and lesser-known incidents in Welsh history, watch rare clips from BBC Wales' own archive, find out about history events in Wales.
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Tracing your Welsh roots? Pick up some tips in our guides.