Here at T+L, we've gotten a bit of a bad rap, because folks seem to think we have some major beef with the lovely city of Philadelphia. Why's that? Well, for a few years now, the City of Brotherly Love has gotten some not-so-favorable results in our annual America's Favorite Cities survey. But I want to remind you: those numbers are entirely based on reader response to our poll, which is open to the public for voting. And I can assure you, we—especially yours truly—are actually quite fond of the sometimes underappreciated city. The only beef we do have with the city comes in the delicious form of a greasy cheesesteak.

That being said, I recently learned about a newly opened project at the 92-acre Morris Arboretum, in northern Philly's Chestnut Hill neighborhood. Though it's a bit of a trek (some 10 or so miles) from the über touristy Old City—home to the Liberty Bell, former City Hall, and Philadelphia Mint, among other historic attractions—this looks to be well worth the trip.

What exactly is this project that has me excited to head south for a weekend soon? A 450-foot long raised walkway through the treetops, that's what. (It soars 50 feet above the ground at its highest point.) Designed by Metcalfe Architecture & Design, not only does this walkway increase the cool factor of the educational arboretum tenfold—visitorship has jumped 66 percent since opening—it's also eco-friendly!

  • The walkway was built entirely using recycled metal and wood.
  • It was designed so that the structure never actually touches the trees, potentially interfering with their natural growth patterns.
  • The foundation was constructed usingmicropiles, so as not to disturb the ever-growing and intricate root systems of the trees.
  • The various sections of the walkway were constructed independently, so as the natural environment grows and changes, sections can be removed/modified/replaced fairly easy to accommodate.

A few other cool features from the project: rope netting that can be used as a hammock to just lay back and gaze up at the canopy looming overhead; and a giant bird nest—built with woven twigs and designed to mirror a Baltimore oriole's nest—complete with three large faux eggs.

So next time you plan a trip to Philadelphia, be sure to add this to your list of must-dos. Just consider the extensive walking retribution for the copious amounts of cheesesteaks you'll be required to ingest while in town.

Admission to the arboretum ranges from $7–14. (See the official site for a detailed breakdown.)

Joshua Pramis is an online associate editor at Travel + Leisure.