At the heart of the Chambord Castle lies its architectural wonder—the double helix staircase. Inspired by Leonardo da Vinci, this spiral staircase features two intertwined staircases coiling around a hollow central axis. Visitors ascending one spiral never cross paths with those descending the other. It services the castle’s main floors and leads up to the terrace, making it both a functional and symbolic centerpiece of Renaissance innovation. It’s one of the most photographed and admired features in the entire castle.