This delightful botanical garden, tucked between the Muséum National d’Histoire Naturelle (see below) and the Seine, is one of our favorite spots for a picnic and a stroll. Created in 1626 as a medicinal plant garden for King Louis XIII, in the 18th century it became an internationally famed scientific institution thanks to naturalist, mathematician, and biologist Georges-Louis Leclerc, Count of Buffon, with the help of fellow-naturalist Louis-Jean-Marie Daubenton. Today the museums are still part academic institutions, but you don’t need to be a student to appreciate these lush grounds.

The garden also harbors a small but well-kempt zoo, the Ménagerie, le Zoo du Jardin des Plantes (www.mnhn.fr; 01-40-79-56-01; 13€ adults, 10€ E.U. students 25 and under, free for children 3 and under; daily 9am–5pm, until 6pm in summer). Created in 1794, this is the oldest zoo in the world. Because of its size, the zoo showcases mostly smaller species, in particular, birds and reptiles. But the healthy selection of mammals (240 to be exact) includes rare species like red pandas, Przewalski horses, and even Florida pumas. If you’re interested in tropical plantlife, don’t miss the park’s Grandes Serres (01-40-79-56-01; 7€ adults, 5€ children and students 4–25, free for children 3 and under; daily Oct–Mar 10am–5pm, Apr–Sept 10am–6pm)—four magnificent 19th-century greenhouses that take you on a botanical journey from the jungle to the desert via a prehistoric plant section and a special area on New Caledonia’s unique vegetation (76 percent of its plants cannot be found anywhere else in the world). It’s fascinating if you’ve got a green thumb, and a good bet on a cold day.