The Cité Plantagenêt is the medieval heart of Le Mans, enclosed within Gallo-Roman walls built in the 3rd and 4th centuries — some of the best-preserved Roman urban fortifications in France. The walls themselves are worth a close look: their decorative brickwork pattern, alternating courses of stone and red tile, is strikingly modern-looking for something nearly 1,800 years old.
Inside the walls, the streets wind uphill past half-timbered houses, Renaissance stone mansions, and small squares. The area around the Place Saint-Michel and the streets running down from the cathedral are particularly well-preserved. This is a living neighbourhood, not a museum — locals use the cafes, and the streets fill on market days and summer evenings. Wear comfortable shoes: the cobbles are historic and uneven.