If the mayor succeeds in shutting down the jail on Rikers Island, the land could become an expansion of LaGuardia Airport, according to one proposal.

Jim Venturi, of Rethink Studio, wants to use the land to expand the existing LaGuardia infrastructure that's just 200 feet away.

His plan would enlarge the concourse and elongate the runways.

"We can turn LaGuardia from a much maligned airport — Joe Biden at one time had called it a third-world airport — into really probably the top urban airport in the world," Venturi says.

His proposal also calls for a new transit depot in port Morris to offer direct transportation to the expanded airport while also connecting travelers to Amtrak, Metro-North and New Jersey Transit trains.

"[The] Second Avenue subway would go to the Bronx, which they proposed in 1968," he adds.

The cost of the proposal and timeline of its completion are not yet determined, Venturi says.