Roman Nîmes is the headline. The Arena, the Maison Carrée, the Tour Magne, and the Castellum Divisorium together make the most complete Roman urban heritage in France. The Musée de la Romanité, opened in 2018 opposite the Arena, ties them together with the city's archaeological collections.
The old town inside the Écusson — the shield-shaped ring of boulevards — is small, walkable, and rewarding for a half-day's wandering between the monuments. Add the Jardins de la Fontaine for an afternoon of formal gardens and Roman ruins, the Carré d'Art for contemporary architecture and exhibitions, and a quiet hour for the cathedral and Museum of Old Nîmes. Combined tickets covering the main Roman sites are excellent value.