If the High Line isn't already a New York icon, it's well on its way to becoming one. Since opening in June 2009, the park that runs for nearly a mile and a half through Manhattan's west side atop a defunct elevated rail line has attracted billions in new developments and legions of curious pedestrians. The park's second phase opened to much fanfare this June, and its first biography is due out in October. High Line: The Inside Story of New York City's Park in the Sky, written by Friends of the High Line co-founders Joshua David and Robert Hammond, even boasts a glowing blurb from Robert Caro — though he offered no insight into what Robert Moses would think of the park.
The High Line's success in New York has sparked a broader discussion about whether or not elevated parks can succeed in American cities in general. Witold Rybczynski, author of Makeshift Metropolis and professor of urbanism at the University of Pennsylvania, recently argued in The New York Times that great elevated parks require a "combination of history and density" unique to places like New York and Paris. (The Promenade Plantée in Paris, a precursor to the High Line, opened on a 2.8-mile viaduct in the 12th Arrondissement in 1993.) If too many cities try to duplicate the High Line concept in less ideal environments, then elevated urban parks will soon join the "dismal record of failed urban design strategies," Rybczynski wrote.
For sure New York's density adds an element of adventure to the High Line that other American cities may lack. (Patrons of the Standard Hotel, which straddles the High Line, have been known to offer peep shows to walkers, for instance.) And few municipalities can afford to spend $153 million (the cost of the first two phases of the High Line) for a park or attract private investments of that level. Still those obstacles haven't kept several cities from pursuing elevated parks of their own. The High Line's success has inspired or encouraged similar projects in Philadelphia (The Reading Viaduct), Chicago (The Bloomingdale Trail), St. Louis (The Trestle), and Jersey City (The Embankment). Here's a look at these four promising elevated parks in progress.