Expanding the train station, the busiest in the nation, is a pressing issue because construction has just begun on a $16 billion pair of rail tunnels under the Hudson River, the centerpieces of a project known as Gateway, which would double the current cross-Hudson capacity.

"Grand Penn" features a public space the size of Bryant Park, a train hall inspired by the original Penn Station, and the relocation of MSG across the street.

Under the plan by the Grand Penn Community Alliance plan, Penn Station will move above ground while Madison Square Garden is relocated.