Mont St Michel is one of the most visited attractions in France and since 1979 has been classed as an UNESCO world heritage site. The great gothic abbey is crowning glory of the medieval walled city which sits in the estuary of the river Couesnon. There is plenty of carparking available and a shuttle bus will take you to within 350m of the city walls or you can make your way there along the walkway. Visit the website for more details.