What do you call a "supertide" that comes every 18 years? Why, the "tide of the century," of course—and it dazzled thousands yesterday in northern France and south-western England, the Telegraph reports. In fact, it momentarily cut off scenic Mont Saint-Michel island from the coast of Normandy, drowning its causeway in water four stories high. And some 20,000 visitors were on-hand to see it, surfing or leaning against a sea-wall and getting drenched by powerful waves. (Not entirely outdone, the River Thames in London did manage to overflow, the Independent reports.) The mega-tide is caused by the "supermoon" effect associated with Friday's solar eclipse, and the alignment of the Earth, sun, and moon that followed.
Officials knew it would be dangerous, and said sandbags and concrete blocks would keep people safe. But tragedy struck when two men drowned, apparently engulfed by rising waters near Ile Grande and Rocher de Saint-Nicolas, Latino Fox News reports. As for Mont Saint-Michel, the rocky isle and UNESCO World Heritage Site has long been of strategic value in France, where troops defended it against the British during the Hundred Years' War and saw assailants stranded by incoming tides, Science Recorder reports. Louis XI later turned it into a prison, and a permanent causeway was built in 1879 to keep rising waters from scouring the island's silt. These days, the medieval walled town and its historic abbey are hotspots for tourists.