Out of the 400 or so of these hidden passageways found across Lyon (some dating back to the fourth century), several are kept open for the public to discover today.
Hidden between various buildings and courtyards in Vieux Lyon and La Croix-Rousse are narrow passageways called traboules. The earliest in Lyon date back to the fourth century, but they were predominantly used in the 19th century silk trade, the heart of which was the Croix-Rousse district. The traboules allowed silk workers to quickly move from place to place across the city, sheltered from the rain. They also played an important part a century later in the Second World War, when Lyon was central in the french resistance against the Nazis: traboules were perfect for escaping and hiding from the Gestapo.
Today, out of the 400 or so traboules in Lyon, several are kept open for the public to discover. Publicly accessible ones are marked with a bronze plaque, so keep your eyes peeled as you walk through Vieux Lyon and Croix-Rousse. The longest one runs between 54 Rue Saint-Jean and 27 Rue de Boeuf in the old town. The door can easily be mistaken for the entrance to a private apartment block but look out for the plaque and head straight through. And starting at 9 Place Colbert you can find a traboule featuring a historic six story staircase.