Mont-Saint-Michel was used in the 6th and 7th centuries as an Armorican stronghold of Romano-Breton 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 AD 460.

Before the construction of the first monastic establishment in the 8th century, the island was called "monte tombe". According to legend, the Archangel Michael appeared to St. Aubert, bishop of Avranches, in 708 and instructed him to build a church on the rocky islet. Aubert repeatedly ignored the angel's instruction, until Michael burned a hole in the bishop's skull with his finger.

The mount gained strategic significance in 933 when William "Long Sword", William I, Duke of Normandy, annexed the Cotentin Peninsula, definitively placing the mount in Normandy. It is depicted in the Bayeux Tapestry which commemorates the 1066 Norman conquest of England. Harold, Earl of Wessex 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.

In 1067, the monastery of Mont-Saint-Michel gave its support to duke William of Normandy in his claim to the throne of England. It was rewarded with properties and grounds on the English side of the Channel, including a small island in the west of Cornwall, which was modelled after the mount, and became a Norman priory named St Michael's Mount of Penzance.

During the Hundred Years' War, the English made repeated assaults on the island, but were unable to seize it due to the abbey's improved fortifications. Les Michelettes – two wrought-iron bombards left by the English in their failed 1423–24 siege of Mont-Saint-Michel – are still displayed near the outer defence wall.

When Louis XI of France founded the Order of Saint Michael in 1469, he intended that the abbey church of Mont Saint-Michel be 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 régime. 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, and the mount was declared a historic monument in 1874. The 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.

Driving is probably the cheapest and easiest way of visiting Mont Saint-Michel, although the queues for entry to the car park are often very long. Within the region of Normandy, drive from Caen along the A84 south-west to Pontorson, then continue a few more kilometres to Avranches. Merge with the D43, following the signs to Mont St-Michel at its end.

Parking costs: €17 (Sep 2023) and is good for 24 hours, no re-entry. This fee includes a shuttle bus from the car park to the foot of the Mont; these buses can get very crowded but the journey is no more five minutes. If you're fit enough to walk 3 km before you start your visit, then follow the flat and well-marked path from your car to the Mont. The views as you approach along the edge of the salt marsh and then across the causeway are spectacular.

Driving times: Paris the total driving time is about 4 hours. Caen about 1½ hours.

Keolis Bus run regular day-trips here Apr-Sept from Rennes (connecting with trains from Paris) and Saint-Malo. For visitors without their own vehicle this will be the most convenient route.

There are no direct train services between Paris and Mont St-Michel, but it is possible to travel to Pontorson by train and then complete the last leg of the journey by bus. The best option is the TGV from Gare Montparnasse to Rennes, where a bus run by Keolis Emeraude (☏ +33 2-99-26-16-70) provides a 90-minute transfer to the island (there are 4 departures from Rennes per day, most departures are timed to match to the arrival of the TGV in Rennes but it is always better to check the timing for last minute changes). The bus station is immediately outside the Rennes train station, at a bus terminal building on your right, after leaving the station by the north exit. The bus costs €12.70, with a reduction to €9.53 for people under 25 or older than 60, and it's free for children under 12. Bus tickets are sold by the driver when boarding the bus, and in advance at the bus terminal. On off-season Sundays, the Rennes connection is often unavailable; take the TGV to Dol-de-Bretagne (listed by RailEurope as DOL, France), then the Keolis bus to Mont Saint-Michel, which costs €6.60 for adults, €4.95 for under-25 or over-60, free for children under 12.

All buses stop at the car park, where you can have transfer to the free Passeur shuttle to get close to the base of the mount. You can also ask the driver if you want to stop at the hostel before Mont St-Michel. The trip into Mont Saint-Michel in the morning can be jammed with traffic. Similarly, expect to be in a traffic jam on the way out as there is only one road leading into and out of the site. During summer, the jam can be up to an hour or more when there are lots of visitors. This meant that you may run a risk of missing your return train to Gare Montparnasse if you are on a day trip from Paris. There is a good chance that the train might wait for the returning bus from Mont Saint-Michel in the afternoon if the timing is slightly off.

Another option is to take a SNCF train to the Pontorson—Mont St-Michel train station (up to 4 a day), with a stopover in Rennes. The 48.55262-1.50491 Pontorson train station.  is no more than 10 minutes from Mont St-Michel by car. Buses between the train station and Mont St-Michel car park are available several times a day and are timed to meet the train. You can also take bus 308 from Granville via Genêts and Avranches to Mont St-Michel.

Parking for bicycles is free, and the ride from Pontorson to the mount is not particularly difficult.

Taxis are prohibitively expensive for long journeys, unless you can split the fare with other travellers. A one-way taxi trip from Mont St-Michel to Rennes will cost about €135. A cheaper option is to take a taxi to the Dol De Bretagne station and change trains at Rennes to get to Paris.

The culinary specialities of Mont Saint-Michel are omelettes, whipped until frothy and light, and saltmarsh lamb (agneau de Pré Salé) dishes from the sheep that wander around the coast. None of the eateries on the island are particularly good (and they are all vastly overpriced) so if you are planning on staying on the mount, you might prefer eating in a town in the surrounding countryside.

The old town at the base of the abbey hosts a wide selection of restaurants, cafés, fast food outlets and other food venues. Mont Saint-Michel is more than slightly a tourist trap with regard to refreshments and travellers' needs - check a number of places for the best deal before ordering. Even then, do not rely on good service.

• Du Guesclin (Grande Rue). On the ramparts with good views out to the sea. The menu touristique, including oysters, omelets and lamb, starts from €17, which is positively cheap by Mont St-Michel standards. 
• 48.635-1.5111111 La Mère Poulard (right at the entrance). World-famous for their omelette. They put non-traditional ingredients into it and cook it right in front of the window of the restaurant. Be careful to make reservations ahead of time because it is usually crowded. Also they only sell their world famous omelette at certain times of the day, so when you make reservations, be sure to make them for the right time if you're intending to get an omelette. €30 or more. (updated Mar 2015)

On the approach road to the mount is a small area of shops, restaurants and supermarkets, although not cheap, they are less un-reasonably priced than getting food on the island. There is also (limited) car parking there.

• 48.55792-1.514461 Camping Haliotis, In Pontorson on the D30 heading towards 'Saint James' or A84, ☏ +33 2 33 68 11 59, fax: +33 2 33 58 95 36, info@camping-haliotis-mont-saint-michel.com. Three-star camping site. (updated Mar 2015)
• 48.59678-1.412412 Camping Saint-Grégoire (In Servon, about 12 km from Avranches and 20 odd from the mont), ☏ +33 2 33 60 26 03, fax: +33 2 33 60 68 65. A two-star camping site with 93 places,; the town nearby has no shops but a couple of restaurants. (updated Mar 2015)

Due to the tourist nature of the mount it can get very busy, especially in high summer. Because of the steep steps up to the abbey, people can sometimes feel unwell, and may want to rest in the numerous gardens throughout the mount with plenty of seats. Keep walking when others are behind you as causing a blockage is likely to annoy them.

Sunday is a good day to avoid visiting the mount as it tends to be the most popular day of the week. It is also best to avoid the middle of the day as coach tours arrive around 10:30 and leave around 16:00, so visiting outside of these hours is advisable to miss the largest crowds.

The local Office de Tourisme is in the Corps de Garde des Bourgeois (the Old Guard Room of the Bourgeois), at the left of the town gates (☏ +33 2-33-60-14-30). Open daily all year except for Christmas Day and New Years Day.

Another helpful tourist office is open during the daytime next to the car park where the free Passeur shuttle buses pick you up. Left luggage lockers are accessible 24-hours, cost €1, and the coin is returned upon retrieving your luggage.