Historian Ruth Goodman and archaeologists Peter Ginn and Tom Pinfold join forces again to take on one of their most ambitious forays into the past: they're heading to France to build a genuine medieval castle. Underway since 1997, Guédelon is a 25-year project where modern craftspeople are using the techniques and materials of the 13th-century. It's a perfect fit for our three intrepid history adventurers, who will experience the magnitude of medieval construction and re-create life as it would have been within the castle's slowly rising walls.