If, as Wallace Stegner said, the national park is “the best idea we ever had,” the rail-trail is certainly a close runner-up. Part transportation corridor, part park, the rail-trail has revolutionized the way America creates high-quality, car-free pathways for bicyclists, runners, walkers, equestrians, and more.It was only a few decades after railroad barons had run roughshod over America’s economy and politics that they began to shed nearly one hundred thousand miles of unneeded r...

For years American urban parks fell into decay due to disinvestment, but as cities began to rebound—and evidence of the economic, cultural, and health benefits of parks grew— investment in urban parks swelled. The U.S. Conference of Mayors recently cited meeting the growing demand for parks and open space as one of the biggest challenges for urban leaders today. It is now widely agreed that the U.S. needs an ambitious and creative plan to increase urban parklands.Urban Green explor...