Once only visited by graffiti artists and the destitute, defunct train tracks were dingy causeways to be avoided. All this is beginning to change. In cities where open space is limited, expensive and scattered, developers and city planners are increasingly seeing old railroads for their hidden potential – land ripe for redevelopment, greenspace and multi-use planning. It's no different here in Atlanta.

The BeltLine is Atlanta's version of Manhattan's aesthetically exquisite High Line garden. In the mid-1900's, Atlanta had approximately 1,000 trains passing through on a daily basis. In fact, the city's original name was Terminus. The tracks that looped the city were known as the Belt Line, a term that now describes the city's $2.8 billion redevelopment project aimed toward revitalizing the 22-mile corridor of primarily obsolete tracks circumnavigating the downtown area. Yesterday, a small section of the BeltLine was the scenery for my morning walk.

Truth be told, many parts the BeltLine are still no more than a dusty trail winding behind city lots…

(Photo courtesy of Christopher T. Martin)

…Or a semi-overgrown railway track.

(Photo courtesy of Christopher T. Martin)

But, when strolling the trail Thursday morning, I couldn't help growing (tentatively) excited by the Atlanta Development Authority's plan.

"The vision is to have a green corridor that varies in width from 60 to 200 feet, that is both a multi-use trail and modern street car or light trail side-by-side," says Ethan Davidson, a spokesman for the Atlanta BeltLine. "The first section of the corridor is now under construction. It's 2.5 miles long and will be complete in early 2012."

(Picture courtesy of Atlanta BeltLine, Inc.)

If all goes according to plan, this huge redevelopment project could help usher in the city's finest hour. It would provide car commuters, cyclists and pedestrians an alternative, and perhaps more pleasant, way to navigate the city. Over the next 20 years, it would also boost the city's greenspace by about 40 percent.

Other cities have similar projects in various stages, including, Seattle's Waterfront, St. Louis' Trestle, Chicago's Bloomingdale Trail, Shellburne Falls' Bridge of Flowers, Jersey City's Harsimus Stem Embankment, and Philadelphia's Reading Viaduct.

Check them out.