With the state mulling the future of the Aqueduct Racetrack in Queens, a giant swath of land near John F. Kennedy International Airport could be the city’s next development frontier.

If Governor Spitzer were to close the track, it could open up an unprecedented opportunity to develop the sprawling 192-acre site in an area that sits next to a subway line, highways, and one of America’s largest airports.

Assemblyman James Gary Pretlow, a Democrat of Yonkers who heads the committee on racing and wagering, said members of the Spitzer administration told his office that shutting down the track was an option they are considering. A horse racing Web site, Bloodhorse.com, last week first reported that Mr. Spitzer was considering closing the storied 113-year-old Aqueduct and shifting the races to nearby Belmont Park. The article caught by surprise numerous legislators involved with the horserace industry and real estate developers.

“It probably is the largest undeveloped hunk of viable real estate in the city,” a professor of urban studies at CUNY’s Queens College, Martin Hanlon, said. “In terms of potential for development, it’s very much there — you have the Belt Parkway, you have the A train.”

The current operator of the Aqueduct, Belmont, and Saratoga racecourses, the New York Racing Association, has a contract that is set to expire at the end of 2007, and the state is currently engaged in choosing from four bidders to award a new contract.

If Aqueduct, which sits just north of the western reaches of JFK, were shut down and opened to new construction, real estate analysts say the giant site, about eight times bigger than the Hudson Yards rail site on the far West Side of Manhattan, could be developed as a regional hub for southeastern Queens, with room for millions of square feet of residential and commercial space.

The city is constantly looking for developable parcels of land to create much-needed housing and office space, and recently detailed sweeping plans to develop a comparatively small 60-acre site next to Shea Stadium at Willets Point.

For years, area legislators and members of the surrounding Ozone Park community by Aqueduct have considered a future without the racetrack, advocating a mostly low-rise residential landscape should the racing industry depart.

The chairwoman of Community Board 10, Betty Braton, said the community has been pushing to change the zoning of the area so as to ensure any development would be within the existing neighborhood context if the Aqueduct were to close.

“That zoning designation poses a lot of problems because it would make a lot of things that a residential community surrounding it would find objectionable,” Ms. Braton said, referring to the potential for big-box retail stores and other types of development.

Council Member Joseph Addabbo, who represents the area, supports the idea of a rezoning, as he said he would like to see development “to mirror what’s preexisting or what fits in the preexisting community.”

The director of sales for southern Queens at Massey Knakal Realty, Stephen Preuss, said development at the Aqueduct site “could really change the landscape of all of South Queens.”

“Development rates right now in that area is anywhere from $50 to $100 a square foot,” Mr. Preuss said. “That could really double or triple that number just for this piece of land.”

Development of the Aqueduct site is highly speculative at this point, legislators say. A court is considering whether the state owns the property, as it claims, or if it belongs to the New York Racing Association, which is in bankruptcy. And while the Spitzer administration’s comments to lawmakers are far from a hard proposal, lawmakers in both chambers and both parties have been quick to lash out and denounce the idea of closing Aqueduct.

“I’m totally opposed to it,” Mr. Pretlow, the chairman of the Assembly’s Committee on Racing and Gaming, said via telephone. “It’s not good for racing — it doesn’t do anything for the entire industry in New York; it hurts the existing venues.”

The legislators representing the district in which Aqueduct is situated offered similar reactions, saying they weren’t consulted about any possible dramatic changes.

“To come in and just unilaterally say it should just be closed is crazy,” state Senator Serphin Maltese said.

A spokesman for Mr. Spitzer, Paul Larrabee, said the state was considering numerous factors as it develops a plan. “Gaming and development are two of the issues that are being considered right now,” Mr. Larrabee said, adding that with the contract set to expire, the state has an opportunity to change the existing model, which has not been working.

Mr. Larrabee said the governor hopes to present a plan for the future of the racing industry soon, before the legislative session ends June 21.

The Legislature and the governor have been looking to overhaul the structure of the racing industry, which has required state subsidies to operate rather than serving as a revenue generator for the state, as it does in many parts of the country.

Earlier this month, casino operator MGM Mirage scrapped its plans to install and manage a video lottery facility at Aqueduct. Lawmakers have pushed for such facilities at both Aqueduct and Belmont in an effort to generate more revenue.

If the Queens facility were to be closed, racing industry officials say hundreds of new horse stalls and other improvements would need to be built at Nassau County’s Belmont Park, a facility that is not equipped for winter racing, as is Aqueduct.

Jeffrey Perlee, CEO of Empire Racing Associates, which has put in a bid to manage the state’s racing franchise once the current contract expires, said a significant structural change is needed.

“The franchise is in desperate need of an infusion of capital — the facilities are quite literally falling apart,” Mr. Perlee said.