Traboules of Lyon

The word traboule, from the Latin trans ambulare, to walk, to pass through, defines passages inside groups of buildings specific to Lyon.

Renaissance buildings were built on the medieval plots, characterized by their "piano key" shape: the long, narrow plots were drawn between two parallel streets. In order to save as much space as possible, there were few cross streets. The traboule thus made it possible to pass from one street to another without having to make a detour. This simple and practical solution was also adopted later on the slopes of the Croix Rousse.

The longest traboule in Old Lyon begins at 54 rue Saint-Jean and ends at 27 rue du Boeuf. It crosses four courtyards and four buildings.
The traboules to see in Old Lyon: 7 and 31 rue St-Jean 18, 42, 50, 52 and 58 rue St-Jean 3 place du Gouvernement (traboule) 1 rue des Trois Maries / 14 quai Romain Rolland 9 rue des Trois Maries / 17 quai Romain Rolland 14 and from 21 to 31 rue du Boeuf 10 and 14 rue de la Bombarde 10-12, rue St-Georges

Source: https://www.lyon.fr/lieu/renaissance-15eme-16eme/les-traboules-du-vieux-lyon