2. Musée d'Orsay (2-3 hours) – one of the best museums in the world. This museum is manageable, you could actually see everything in under 3 hours! Plus it stays open late until 9:45 pm on Thursdays so you don’t have to miss good weather to see it all. This railway turned museum is filled will French Impressionist paintings and sculptures by Monet, Manet, and the likes. This site is closed on Mondays. Use your Paris Museum Pass to skip the line!