1st Arrondissement Museums and Galleries
Musée des Arts Décoratifs
107 Rue de Rivoli, 1st
Located in the Western wing of the Louvre, this is where you'll find Aubusson carpets, plenty of Lalique, hand-painted ceramics, and Jeanne Lanvin's interiors. While the collection spans back to the 13th century, it also includes more contemporary furniture designers, too.
Musée du Louvre
Musée du Louvre, 1st
In its original 12th-century incarnation, the Louvre was a fortress (you can still see remnants of this down in the crypt); it morphed over the years into a larger and larger palace until Louis XIV decamped to Versailles and left it to house the royal collection (which already included Leonardo da Vinci's Mona Lisa, which was brought into the fold by Frances I in the mid 1500s). It didn't assume its museum status until after the French Revolution, at which point its acquisition pace quickened intensively: The museum has almost 400,000 pieces, of which about 35,000 are on display at any given time. And there's very little filler or fluff in the mix. While the crowds queue up around I.M. Pei's glass pyramid, you can buy advance tickets online. Though it's theoretically possible to marathon your way through the museum in one swoop, we strongly recommend scattering a few short(er) visits across the length of your stay. We haven't tried it, but we hear great things about THATLou—they organize treasure hunts through the museum.