Back to school, put away the flip-flops, get out the sneakers... and explore the capital's hidden treasures! Head for the European Heritage Days on September 20 and 21, 2025, when museums, castles and unusual spots open their doors wide. In Paris, don't miss the Maison La Roche, a modernist masterpiece by Le Corbusier, to be (re)discovered in the chic 16th arrondissement.