Connected to France by a bridge, Isla De Ré is an island unlike any other. It's just 15 miles long and three miles wide, and its unique size and location see it welcome countless visitors every single year. However, tourists have been careful when they visit this place - and it's suggested that they avoid the water at all costs. That's because this island is home to a strange natural phenomenon rarely seen elsewhere.
In the summer, this island is home to Sinusoidal waves, which make a cross-hatch pattern in the water. And while these look cool, they're extremely deadly as the currents are strong and unpredictable.