This converted railway station on the banks of the Seine is the place to see all the Impressionists (they're upstairs, knee-deep in visitors). Watch out for particularly horrific queues on Tuesday, when other Paris museums and galleries are closed.
1 rue de la Legion d’Honneur; Tel: 01 45 49 11 11;
Metro: Solferino; closed on Mondays/ www.musee-orsay.fr/
Don't miss the museum restaurant, either. Absolutely stunning and the food was wonderful, too.