New York City is not the only urban center in the United States with an elevated railway like the High Line.
In Philadelphia, an old freight and passenger rail line called the Reading Viaduct winds above the streets and between buildings just north of the city’s center. Just like the High Line, the trains stopped running decades ago, and since then nature has taken over the tracks. The self-seeded landscape has inspired some local residents to join together to advocate for the historic structure to be transformed into public open space.
We took a field trip to Philadelphia on October 20 to walk the line, observe the wild landscape, and share ideas with Paul vanMeter and Liz Maillie of Viaduct Greene, the non-profit dedicated to creating a new public park on the structure. Follow us after the jump for photos and more.
VIEW PHOTOS  from our walk.
Here are some of the interesting facts we learned:
- The Reading Viaduct is located in an area nicknamed “The Eraserhood,” which is a reference to film director David Lynch, who has said the area’s industrial cityscape served as inspiration for his movie, Eraserhead.
- The Reading Viaduct is three miles in length. That is double the length of the High Line!
- The Reading Viaduct consists of two branches of railway: the 9th Street Branch and the City Branch.
- City Branch carried freight to and from the city, including newsprint for the Philadelphia Inquirer. The trains stopped running in 1992 after the newspaper, its last customer, moved its print shop to the suburbs.
- The two branches of the Reading Viaduct are privately owned by separate corporate entities.
- Unlike the High Like, parts of the Reading Viaduct are submerged below city streets, running through tunnels and between building foundations.
- A lot of plant species original to the High Line's self-sown landscape are also growing on the Reading viaduct: big bluestem grass (Andropogon), joe pye weed (Eupatorium) and evening primrose (Oenothera).
- Some plants that they have and we never did: butterfly bush (Buddleia), which is a prolifically flowering shrub that is often used in gardens to attract butterflies; gooseberries (Ribes uva-crispa); and empress tree (Paulownia tomentosa).
- Empress trees are a non-native plant that came to the United States from China. The seed pods were used as packing material for imported goods, so you often see empress trees growing along rail lines in the US where the packing materially was dumped. Empress trees are/were conspicuously missing from the High Line landscape, probably because the High Line was primarily used to transport food from Upstate New York rather than imports from other parts of the world.
You can also read some of the recent press the project has received.
The King of Center City 
Philadelphia City Paper, October 6, 2011
NYC High Line inspires Philly to redevelop viaduct 
CBS News, October 17, 2011
Viaduct district plan wins Council OK 
Philadelphia Inquirer, October 27, 2011
Philly's Reading Viaduct & NYC's High Line 
WHYY Radio, Radio Times, November 2, 2011