The best known planted railway line is, of course, the High Line in New York, open from dawn to dusk every day, and offering a very different and very beautiful elevated perspective of the city.  The first stage opened in 2009 and the 1.5 mile walk was completed in 2014. What makes it truly spectacular is the inspired perennial planting by Piet Oudolf who "translated the magic of the self-seeded landscape of the derelict railway into what you see today".