The original Penn Station, designed by McKim, Mead & White and completed in 1910, was a sky-lit, Beaux-Arts masterpiece. The adaptive reuse of the Farley Building—also designed by McKim, Mead & White and completed in 1913—represents the transformation of an underutilized building into a new, inviting front door for New York. The Main Concourse, located in the Farley Building’s former mail sorting room, is designed with a dramatic skylight that traverses the entire space—reflecting the design of the original Penn Station.

The skylight is arranged in four catenary vaults, which each comprise more than 500 glass and steel panels that come together to form a moiré effect. At the edges of each vault, the panels thicken to sustain greater structural loads, while at the apexes, which rise 92 feet above the concourse, the panels' depth lightens to enhance the airy ambience of the space. To support the skylight, three massive, original steel trusses, which were invisible to the postal workers a century ago, were uncovered and have become a major focal point of the design.

With web-like structures, each bolted truss adds an extra sense of lightness—establishing a modern aesthetic while displaying the workmanship of the original structure. Moynihan Train Hall, which is targeting Silver certification in the new LEED for Transit category from the U.S. Green Building Council, connects to nine platforms and 17 tracks that primarily serve Amtrak and the Long Island Rail Road. It connects directly with the Eighth Avenue Subway, and plans are in the works to connect the entire Penn Station complex, including Moynihan Train Hall, to MetroNorth and AirTrain JFK.