Meet Joshua David and Robert Hammond, a travel writer and painter, respectively. A few years ago they were strangers, both searching for the same thing: a way to help save the High Line, the abandoned elevated rail line that runs along 22 blocks of Manhattan’s West Side. Fast-forward six years and they are business partners occupying a sleek office in the Meatpacking District. They hobnob with socially conscious celebrities like Edward Norton, Kevin Bacon, and Kyra Sedgwick, and have the enthusiastic financial support (more than $51 million) from the City of New York necessary to complete one of the city’s most ambitious and far-reaching urban-redesign schemes in years. It’s not exactly what David and Hammond were expecting when they sat next to each other at a 1999 community meeting about the future of the High Line.

“If you asked me five years ago if I would be doing this full-time, I wouldn’t have believed it, nor would I have wanted to,” says Hammond. “We were both just looking for a way to be supportive—stuff envelopes, give a hundred bucks,” adds David.

But what they discovered that evening, and during the following year, was that there was no formal organization set up to preserve this slice of New York’s industrial history. Worse yet, the end was imminent, with then Mayor Giuliani signing a demolition order. So with absolutely no relevant experience, the two neighborhood activists put their careers on hold and formed the nonprofit Friends of the High Line (FHL) with a simple goal: “To spark a dynamic public debate,” says David. “And more importantly, to see people up there.”

By late 2007, if all goes as planned, they will get their wish. After overcoming a number of hurdles—including taking the Giuliani administration to court in 2001 and winning—the FHL hired the landscape architecture firm Field Operations and architects Diller Scofidio + Renfro to create a plan to convert the structure into a public park. The first stage of their “agritecture” proposal, which includes a series of flexible planks interspersed with wetlands, sunken overlooks, and floating ponds, is currently on display through October at the Museum of Modern Art. “The team is incredibly intelligent, creative, and thoughtful,” says David. “They have a unique approach to the High Line as a structure and a landscape that is a single functioning entity. One doesn’t dominate the other.”

When completed, the new and improved High Line will add much-needed green space to a city that’s desperate for it. According to the Trust for Public Land, New York City averages only 4.6 acres per 1,000 residents, compared with the national average of eight. More important, at least according to David, the completion of the High Line will bring about “a level of architectural innovation unlike any other urban condition in the city, the country, the world.” Already in the works along the High Line are the André Balazs Standard hotel, a gallery designed by Deborah Berke, and a Frank Gehry residential complex.

While unusual, the High Line isn’t the first project of its kind to be undertaken by a major city: In the early 1990s, Paris unveiled the Promenade Plantée, which also occupies the site of a former elevated railway. With this as a model, the High Line organizers learned how to get people up and down from the site in a safe and appealing way, and also to plan for extremely high levels of pedestrian traffic—something, according to David, that the designers of the Promenade Plantée didn’t anticipate. But the most crucial lesson David and Hammond learned from their predecessor, according to David, is, “If you build a park in the sky, somebody will come.”

For more information on Friends of the High Line, visit www.thehighline.org. Groundbreaking is scheduled for later this year, with the first phase scheduled for completion late in 2007.