Designed for 9 to 12-year-olds, and supporting aspects of key stages 2 and 3 of the history curriculum, it illustrates the effects of the Norman conquest on Wales. It focuses primarily on the period’s most enduring legacy, the castles. Viewers learn that the original Norman structures were inadequate to subjugate the Welsh. Stronger, stone fortresses were needed. The largest of these, Gilbert Declary’s Caerphilly, is still one of Europe’s biggest castles.

Far more impregnable than the native Welsh prince’s square keeps, the Norman concentric castles emphasised that the conquest was permanent. As Heritage Theatre illustrates in the film, the Welsh attempted to fight back, but they could not match the Normans’ military prowess.

Recreated siege engines, in action at Caerphilly, depict how the Normans crushed their enemies, and although much of north and west Wales remained independent for over 200 years after 1066, the coronation of Edward I of England heralded the end of Welsh resistance.

After defeating Llywelyn, the last native-born prince of Gwyned in 1282, Edward began a major castle-building programme, almost bankrupting the English crown in the process. His legacy, the castles and medieval towns of Conway, Caernarvon and Beaumaris all built within a day’s march of each other have since become major tourist attractions. But 800 years ago their architect, James of St George, built them simply to keep the locals out.

The film also gives an insight into the economics of the period. The Welsh stone mason received three pence a day, while his Norman counterpart, working for King Edward, earned five pence per foot.

Filmed on location at a variety of Welsh castles, the video also includes theatre in education and role play by pupils. It captures the ethos of the period and is a valuable insight into the effects of the Norman conquest on Wales.

Castles Alive, Pounds 9.95 from Cadw, Brunel House, 2 Fitzalan Road, Cardiff CF2 1UY. Tel: 0222 465511