James (1230-1308) was Europe's greatest castle builder, commissioned by Kings of France and England to oversee the construction of new fortifications.

He perfected the symmetrical, concentric 'walls within walls' design that characterised castles of that period.

He brought with him an army of artisans and skilled labourers - Europe's finest masons and carpented. Up to 2000 skilled labourers could be working at any one time - quarrymen, woodcutters, smiths, miners, ditchers, carters, and joiners.

Many of his castles remain in excellent condition today; with practical demonstrations by military experts and architectural historians we will analyse exactly what made these castles so formidable, an impregnable symbol of the monarch's power.