One of the most relaxed and beautiful beach towns on the Côte d’Argent (Silver Coast), the thin strip of sand that runs along 200km of France’s southern Atlantic seaboard, Arcachon was created a mere 160 years ago by French aristocrats suffering from bad lungs and boredom. It remains a posh resort town, and a hotspot for vacationing families and content retirees. But more than its dozens of beaches, what makes Arcachon worth a daytrip from Bordeaux is the TDune du Pyla, Europe’s highest sand dune and a slice of the Sahara in France. It’s an absolute must-see. The Bassin d’Arcachon (bay of Arcachon) is also known for the Banc d’Arguin, a 1000-acre sand bar in the form of a crescent across the waters from the Dune. Pack a picnic lunch, hop the train and prepare to play in white sand and swim in the azure water.