Two of Paris's oldest and famous gardens are the Tuileries Garden, created from the 16th century for a palace on the banks of the Seine near the Louvre, and the Left bank Luxembourg Garden, another formerly private garden belonging to a château built for the Marie de' Medici in 1612. The Jardin des Plantes, created by Louis XIII's doctor Guy de La Brosse for the cultivation of medicinal plants, was Paris' first public garden.
A few of Paris' other large gardens are Second Empire creations: the formerly suburban parks of Montsouris, Buttes Chaumont and Parc Monceau (formerly known as the "folie de Chartres"), were creations of Napoleon III's engineer Jean-Charles Alphand and the landscape . You will often see Parisians having picnics at the parks, soaking up the warm sunshine, or simply enjoying the nature. They are peaceful escapes from the city and are enjoyed by all ages. Another project executed under the orders of Baron Haussmann was the re-sculpting of Paris' western Bois de Boulogne forest-parklands; the Bois de Vincennes, to Paris' opposite eastern end, received a similar treatment in years following.
Newer additions to Paris' park landscape are the Parc de la Villette, built by the architect Bernard Tschumi on the location of Paris' former slaughterhouses, and gardens being lain to Paris' periphery along the traces of its former circular "Petite Ceinture" railway line.
Source: Wikipedia