The Louvre, which saw approximately 8.5 million visitors in 2009 is among several Paris museums open free to the public the first sunday of every month. The  Louvre, which hosted recently such successful temporary exhibits as  "Les portes du Ciel" with 250,000 visitors, is considered the world's most popular museum. In related news the Eiffel Tower posted a drop from 6.9 to 6.6 million visitors last year. This was the first decline in five years. Following is a list of "first sunday" free museums in Paris:

Musée du Louvre, 75001 Paris

Musée de l'Orangerie, Jardin des Tuileries - 75001 Paris

Musée Picasso, Hôtel Salé - 5, rue de Thorigny - 75003 Paris

Musée du Moyen-Age (Thermes de Cluny) 6, Place Paul-Painlevé - 75005 Paris

Musée d'Orsay, 1, rue de la Légion d'Honneur - 75007 Paris

Musée national d'art moderne, 19, rue Beaubourg - 75004 Paris

Musée de Versailles et de Trianon, 78000 Versailles

Musée du Château de Fontainebleau, 77300 Fontainebleau