#1 Dune du Pilat (Arcachon)
The Dune du Pilat is a massive sand formation on the Atlantic coast of France, located about 60 km southwest of Bordeaux. Stretching 3 km long and 600 meters wide, it reaches 115 meters in height, making it the tallest dune in Europe. Millions of visitors climb its slopes annually for expansive views of the ocean, forests, and marshes.