The Louvre is not a museum you finish, it is one you play strategically: enter through the quiet door, start where the crowds don’t, and let the Mona Lisa come last if she comes at all. Do that and the world’s most visited museum feels almost private.
Enter via the Carrousel du Louvre mall rather than the pyramid, and book a timed ticket. Wednesday and Friday evenings run late and feel half as busy as any daytime slot.
Palais Royal–Musée du Louvre station drops you at the Carrousel entrance. The Tuileries, Sainte-Chapelle and the Marais are all walkable follow-ons.