The island of Mont-Saint-Michel in Normandy, France

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A towering tidal island. Mont-Saint-Michel

The stunning sight of Mont-Saint-Michel rising out of the bay is unforgettable. But you have to get the timing right if you want to visit the island. The paved causeway is accessible only when the tide is out; otherwise, you’re at the mercy of the muddy flats, quicksand and a rising tide.

Today's visitors are following in the footsteps of pilgrims who, for centuries, crossed Europe to pray at the sacred site. The bishop of Avranches built a chapel on this rock in 708 after being visited in a dream by the archangel St Michael. And the rest, as they say, is history. Now the island, half a mile off the coast of Normandy in north-west France, is a Unesco World Heritage Site. Its permanent population is fewer than 50 people, including a dozen or so monks and nuns, but more than 3 million visitors make the island crossing each year.