Bishop Aubert of Avranches is said to have built a devotional chapel on the summit of the island in 708, following his vision of the Archangel Michael, whose gilded figure, perched on the vanquished dragon, crowns the tip of the abbey’s spire. In 966, Richard I, Duke of Normandy, gave Mont St-Michel to the Benedictines, who turned it into a centre of learning and, in the 11th century, into something of an ecclesiastical fortress, with a military garrison at the disposal of both abbot and king.
In the 15th century, during the Hundred Years War, the English blockaded and besieged Mont St-Michel three times. The fortified abbey withstood these assaults and was the only place in western and northern France not to fall into English hands. After the Revolution, Mont St-Michel was turned into a prison. In 1966, the abbey was symbolically returned to the Benedictines as part of the celebrations marking its millennium. Mont St-Michel and the bay became a Unesco World Heritage Site in 1979.
In recent decades, sand and silt built up hugely around the causeway – created in 1879 – linking the Mont to the mainland, threatening to turn the island into a permanent peninsula. To restore the site’s ‘maritime character’, in 2014 the causeway was replaced by a 2km pedestrian and vehicle (primarily the shuttle buses) bridge designed to allow the tides and the River Couësnon (kweh-no) – whose new barrage (dam) stores up high-tide water and then releases it at low tide – to flush away accumulated sediments. For the latest, see www.projetmontsaintmichel.fr.