1. Musée d'Orsay Paris, France
www.musee-orsay.fr
Claim to Fame: Paris' other great art museum
You'd think being the second most famous museum in Paris would be something of a sore spot. But the Musée d'Orsay doesn't suffer for comparison to the Louvre; in fact, when the d'Orsay was created in 1986, the Louvre transferred its entire post-1848 collection here. In other words, it's the Louvre's modern complement and features art created up to 1914. If you want to see a world-class Impressionist collection in a beautiful, well-lit setting, you will be happy as a clam here.
The Louvre is closed on Tuesday, which means every hapless tourist who doesn't know this will wind up at the d'Orsay instead (Translation: sweaty crowds). If this is your first time and you prefer an irreverent museum experience, try Rick Steves' Paris 2007, a guide book which leads you through the d'Orsay with some entertaining context. Goofy American alert: Others in the building may be using Steves' guide, giggling in the same places you are. Be discreet.