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

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A saintly vision inspired the first chapel. Mont-Saint-Michel

Rising majestically out of the bay, Mont-Saint-Michel is once again a true island, at least during high tides. A crude, elevated causeway built in the 19th century once connected Mont-Saint-Michel to the mainland, allowing visitors to walk across to the spectacular rock. But in 2014, the causeway was removed and replaced by an elegant, curving bridge above the tidal flats. Now water flows freely around the monument at high tide, making the tiny island fortress a real island for the first time in more than a century.

Today's visitors are following in the footsteps of pilgrims who for centuries traversed Europe to pray at the sacred site. The local bishop of Avranches built a chapel on this rock in 708 after the archangel St. Michael visited him in a dream, and the rest, as they say, is history. Now the island, half a mile off the coast of Normandy in northwestern 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 cross over to the island most years.