Mont-Saint-Michel
The church atop Mont-Saint-Michel was established as early as the eighth century, and if you ask the appropriate people, you'll learn that it was built by the Archangel Michael himself. Other houses and streets were built on the steep slopes alongside it throughout the years, until Mont-Saint-Michel finally formed a small town and was designated a UNESCO World Heritage Site.
Today it has been a major pilgrimage destination for centuries, not to mention a hit with the tourists. It lies in the bay where Brittany and Normandy merge, seemingly free-floating on days of high tide. For hundreds of years, the causeway between the mont and the mainland was only uncovered at low tide. These days there is a light bridge crossing which allows the ocean to ebb and flow around it, only covering the path on the occasional “supertide”.
Location: Normandie, France