Louvre Museum, Paris

The world's most visited museum, in the former royal palace on the Seine, entered through I. M. Pei's glass pyramid. Its collection runs from ancient Egypt and Greece to the 19th century, with the Mona Lisa, the Venus de Milo, the Winged Victory of Samothrace and Napoleon's apartments among thousands of masterpieces.

Timed tickets must be booked online, and even then expect crowds around the Mona Lisa. Pick a few wings rather than trying to see it all. It's closed on Tuesdays and open late on some evenings, which are quieter. The Tuileries Garden leads from the museum towards the Place de la Concorde.