The pedestrian streets of old Troyes are an immersion into the medieval era of the city, which holds one of the richest collections of half-timbered houses in France. Their characteristic vertical, horizontal, or diagonal beams reveal the wooden skeleton of the buildings. Some streets are still as narrow as they were during the Middle Ages. The ruelle des Chats (Cats lane) hold its name from the fact that cats can cross it in one jump, from one roof to another. Its houses being so close together, this street never sees the sunlight.