Since Paris is such a compact city (roughly 6 miles across), much of it can be covered on foot — especially the primary sightseeing spots in the city's center. There will be times, however, when a métro or bus ride is welcome. Some of the métro stations are worth a visit. For example, the stop for the Louvre (line 1) gives one the impression that the train has pulled into the Museum itself: the immaculate marble walls are lined with exhibits and replicas of art works, with glass cases containing various sculptures. On line 13, Varenne offers exhibits from the nearby Rodin Museum (including a replica of The Thinker), while Liège is paneled with beautiful tiles. Abbesses (line 12) features murals alongside its spiral staircase leading to one of the more elaborate of Art Nouveau entrances.