This week on the Post we have gardens and planting on abandoned railways lines. The first project of its type was the Promenade plantée or Couleé verte René-Dumont along the former Vincennes railway line viaduct in the 12ème arrondissement of Paris. It is 4.7km long and was opened in 1993. It provides a peaceful green or, in autumn, golden walkway ten metres above street level. There are plans to extend it to link up with the disused circular Petite Ceinture which features in Proust's A la recherche du temps perdu.