The Mont Saint-Michel is a stunning tidal island in Normandy, France, famous for its dramatic location and its medieval architecture, which includes the beautiful Abbey of Mont Saint-Michel. Under the abbey and its main church is a secret world of crypts and chambers, built to support the mass of the abbey or dug in the rock. In this story, we will explore more than a thousand years of history, along which this medieval wonder formed. From christianisation to viking raids and medieval monasticism, from Anglo-French wars to architectural styles, we have a lot to discover.