Transformed from an unused train viaduct, this beautiful aerial garden walkway runs from the place de la Bastille to the Bois de Vincennes. The 4.5km (2.8-mile) pedestrian path traces flower gardens, tree bowers, rose trellises, and fountains and takes you over the 12th arrondissement, past the Gare de Lyon, and through the Reuilly Gardens (home to fizzy drinking-water fountains). At ground level along avenue Daumesnil, the brick archways now shelter the Viaduct des Arts, a series of galleries and workshops that show off the work of highly skilled artisans.