Musée d'Orsay

This is what happens when you save a train station from the wrecking ball: you get the most beautiful museum in Paris. The Gare d'Orsay was built for the 1900 World's Fair, but its platforms were too short for modern electric trains by the 1930s, and it sat empty for decades. It served as a prisoner-of-war reception center, a film set (Orson Welles shot his adaptation of Kafka's The Trial here), and a temporary auction house before President Valéry Giscard d'Estaing decided in 1977 to turn it into a museum.

The collection picks up where the Louvre leaves off. If the Louvre is the establishment, the Orsay is the rebellion — it houses the Impressionists, the Post-Impressionists, and all the artists the academic establishment tried to destroy. Monet, Renoir, Degas, Cézanne, Van Gogh, Gauguin, Toulouse-Lautrec — they're all here. Many of these paintings were originally rejected by the official Paris Salon and shown at the Salon des Refusés, a sort of "reject exhibition" that accidentally launched modern art.

Don't miss the giant clock faces on the upper level — they're the original station clocks, and standing behind them you get one of the best views of Montmartre and the Sacré-Cœur through the translucent glass. The clock on the Seine side has become one of the most photographed spots in Paris.

The building itself is an artwork. Architect Victor Laloux covered the iron and steel structure with ornate stone facades because the Beaux-Arts establishment thought exposed metal was ugly — the exact opposite of what Eiffel had done eleven years earlier. It's engineering pretending to be sculpture.