Park Avenue Viaduct

The Park Avenue Viaduct is a roadway in the Manhattan borough of New York City that carries Park Avenue from East 40th to 46th Streets around Grand Central Terminal and the MetLife Building, then through the Helmsley Building; all three buildings lie across the line of the avenue.The viaduct was listed on the National Register of Historic Places in 1983, technically as a "boundary increase" to the Grand Central Terminal's prior listing, but carrying a separate reference number.DescriptionThe viaduct provides a pedestrian-, bicycle-, and bus-free express route for taxicabs and other automobile traffic from 40th Street to 46th Street. From the south, traffic from Park Avenue or the Park Avenue Tunnel enters a ramp which rises to a "T" above 42nd Street, over the street-level entrance to Grand Central Terminal below; Pershing Square, the side ramps of Park Avenue at this point, descend from 40th to end at 42nd Street.The elevated roadway then passes in front of Grand Central Terminal and around it to the east, passing the MetLife Building and descending again to ground level through the east portal in the Helmsley Building, arriving at 46th Street. Traffic coming from the north reverses this pattern: up a ramp through the Helmsley Building's west portal, past the MetLife Building, around the left to the front of Grand Central, and then to the right and down again to 40th Street, meeting side lanes coming from 42nd Street, where the viaduct connects to the Park Avenue Tunnel or to Park Avenue proper.