The streetspace beneath the Metro North elevated tracks between 111th and 133rd Streets in Manhattan could be converted into "a High Line for Harlem," according to a position paper by David Giles published this month by the Center for an Urban Future.

The proposal was originally made by Irwin Cohen, the creator of the very popular Chelsea Market on 15th Street west of Ninth Avenue, to the Harlem Community Development Corporation that had approached him with the hope of convincing him to redevelop La Marqueta, two "moribund" buildings beneath the tracks between 111th and 113th Streets.

Mr. Cohen suggested, instead, "something much bigger": "I told him it doesn't mean anything to develop three blocks, but just think about a mile of La Marqueta, 60 feet wide, with all family-run businesses...a fantastic graduate school for people to learn to run businesses and to develop sustainable family wealth."

The Harlem Community Development Corporation liked the idea and commissioned Meta Brunzema, an architect, to sketch an initial plan.

"The proposal is wonderfully simple," Mr. Giles wrote, adding that "it would dispense with the concept of an interior, temperature-controlled market altogether and replace the old La Marqueta buildings with free-standing commercial stalls that would use the Metro North tracks as a detached roof, much like you find in traditional European markets like La Boqueira in Barcelona, or the recently refurbished Borough Market in London (also situated under an elevated train line)."

His article said that Ms. Brunzema has proposed "a small amphitheater dug into the street at 116th Street, pedestrian paths curving from one side of the viaduct to the other, and dense clusters of stalls opening up to broader un-programmed spaces." "Like the High Line or perhaps Chelsea Market, it also combines a wide array of different materials, including - in one area - steel shipping containers carved up and tilted at slight angles to form vendor stalls, patches of slate paving stones, and columns of crushed glass," Mr. Giles continued, adding that "once finished, the market could house as many as 900 vendors in small stalls ranging from 80 square feet to 160 square feet."

Mr. Giles said that the four zip codes that make up Central and East Harlem have about 42 stores for every 10,000 residents as compared to the Upper East Side that has about 132 stores for every 10,000 residents.

His article said that Tom Lunke of the Harlem Community Development Corporation has estimated that the mile-long market would cost about $215 per square foot or about $44 million. "That isn't peanuts, but it's a fraction of the cost of the High Line, which came in at $880 per square foot, for a total of $176 million," according to Mr. Giles.

Earlier this month, a greenmarket opened at the World Financial Center at Battery Park City.

According to an article by Joseph Rearick in last week's edition of the Downtown Express, the market will operate in the plaza outside Two World Financial Center at 225 Liberty Street every Thursday until Thanksgiving.

The World Financial Center Greenmarket is the latest project undertaken by Grow NYC, a not-for-profit that organizes dozens of greenmarkets around the city. Grow NYC's greenmarket director, Michael Hurwitz, along with representatives from Brookfield Properties, owner of the World Financial Center, and a host of local politicians, welcomed 10 vendors and a few eager customers to the market's inaugural session.

New York State Assembly Speaker Sheldon Silver spoke about the significance of the greenmarket's introduction after the World Trade Center greenmarket, once open on Tuesdays and Thursdays beside the Twin Towers, was made impossible by the attacks of September 11th, the article said, adding that "He called the greenmarket 'a testament to the spirit of residents who have revived the greenmarket we lost on September 11th.'"

There is another greenmarket nearby at Zuccotti Park, but officials said it had limited space.