The island lies approximately one kilometer (0.6 miles) off the country’s northwestern coast, at the mouth of the Couesnon River near Avranches and is 7 hectares (17 acres) in area. The mainland part of the commune is 393 hectares (971 acres) in area so that the total surface of the commune is 400 hectares (988 acres).
The commune’s position—on an island just a few hundred metres from land—made it accessible at low tide to the many pilgrims to its abbey, but defensible as an incoming tide stranded, drove off, or drowned would-be assailants. The island remained unconquered during the Hundred Years’ War; a small garrison fended off a full attack by the English in 1433. Louis XI recognised the reverse benefits of its natural defence and turned it into a prison. The abbey was used regularly as a prison during the Ancien Régime.
Mont Saint-Michel and its bay are on the UNESCO list of World Heritage Sites. It is visited by more than 3 million people each year. Over 60 buildings within the commune are protected in France as monuments historiques.
The original site was founded by an Irish hermit, who gathered a following from the local community. Mont-Saint-Michel was used in the sixth and seventh centuries as an Armorican stronghold of Gallo-Roman culture and power until it was ransacked by the Franks, thus ending the trans-channel culture that had stood since the departure of the Romans in 460. From roughly the fifth to the eighth century, Mont Saint-Michel belonged to the territory of Neustria and, in the early ninth century, was an important place in the marches of Neustria.Inside the walls of Mont Saint-Michel
Before the construction of the first monastic establishment in the 8th century, the island was called Mont Tombe (Latin: tumba). According to a legend, the archangel Michael appeared in 708 to Aubert of Avranches, the bishop of Avranches, and instructed him to build a church on the rocky islet.
Unable to defend his kingdom against the assaults of the Vikings, the king of the Franks agreed to grant the Cotentin peninsula and the Avranchin, including Mont Saint-Michel traditionally linked to the city of Avranches, to the Bretons in the Treaty of Compiègne (867). This marked the beginning of a brief period of Breton possession of the Mont. In fact, these lands and Mont Saint-Michel were never really included in the duchy of Brittany and remained independent bishoprics from the newly created Breton archbishopric of Dol. When Rollo confirmed Franco as archbishop of Rouen, these traditional dependences of the Rouen archbishopric were retained in it.
The mount gained strategic significance again in 933 when William I Longsword annexed the Cotentin Peninsula from the weakened Duchy of Brittany. This made the mount definitively part of Normandy, and is depicted in the Bayeux Tapestry, which commemorates the 1066 Norman conquest of England. Harold Godwinson is pictured on the tapestry rescuing two Norman knights from the quicksand in the tidal flats during a battle with Conan II, Duke of Brittany. Norman ducal patronage financed the spectacular Norman architecture of the abbey in subsequent centuries.Bayeux Tapestry scenes 16 and 17: William and Harold at Mont Saint-Michel (at top centre); Harold rescuing knights from quicksand
In 1067 the monastery of Mont Saint-Michel gave its support to William the Conqueror in his claim to the throne of England. This he rewarded with properties and grounds on the English side of the Channel, including a small island off the southwestern coast of Cornwall which was modelled after the Mount and became a Norman priory named St Michael’s Mount of Penzance.Cannons abandoned by Thomas de Scales, 7th Baron Scales at Mont Saint-Michel on 17 June 1434. As of June 2013 only the second cannon, the one closer to the wall, is on display inside the entrance to the Mont’s outer wall.
During the Hundred Years’ War, the Kingdom of England made repeated assaults on the island but was unable to seize it due to the abbey’s improved fortifications. The English initially besieged the Mont in 1423–24, and then again in 1433–34 with English forces under the command of Thomas de Scales, 7th Baron Scales. Two wrought-iron bombards that Scales abandoned when he gave up his siege are still on site. They are known as les Michelettes. Mont Saint-Michel’s resolute resistance inspired the French, especially Joan of Arc.
When Louis XI of France founded the Order of Saint Michael in 1469, he intended that the abbey church of Mont Saint-Michel become the chapel for the Order, but because of its great distance from Paris, his intention could never be realized.
The wealth and influence of the abbey extended to many daughter foundations, including St. Michael’s Mount in Cornwall. However, its popularity and prestige as a centre of pilgrimage waned with the Reformation, and by the time of the French Revolution there were scarcely any monks in residence. The abbey was closed and converted into a prison, initially to hold clerical opponents of the republican regime. High-profile political prisoners followed, but by 1836, influential figures—including Victor Hugo—had launched a campaign to restore what was seen as a national architectural treasure. The prison was finally closed in 1863. In 1872, the highly decorated French architect of historic monuments, Edouard Corroyer, was responsible for assessing the condition of the Mont. It took him about two years to convince his minister to classify Mont Saint-Michel a historic monument, and it was officially declared as such in 1874. From then on, this highly qualified and educated architect, member of the Academy of Fine Arts, devoted himself entirely to the restoration of “la Merveille”. Under his direction, gigantic works were undertaken, starting with the most urgent.
Édouard Corroyer devoted fifteen years of his life to this work and wrote four works on the building. The name of Edward Corroyer remains forever attached to the “resurrection” of Mont Saint-Michel.
Mont Saint-Michel and its bay were added to the UNESCO list of World Heritage Sites in 1979, and it was listed with criteria such as cultural, historical, and architectural significance, as well as human-created and natural beauty.