It’s an interesting choice for a postcard: a picture of a curve in one of the “Hudson Tubes,” as they used to be called, that carried trains ferrying passengers from 33rd Street in Manhattan to Hoboken and Jersey City.
Opened in 1908 by the Hudson and Manhattan Railroad, they’re the same cast-iron tunnels PATH trains use today.
So where exactly is this curve, noteworthy enough to put on a postcard?
It may be just past the Christopher Street station on the way to New Jersey. A February 26, 1908 New York Times article chronicling the first train ride out of Manhattan in the new tunnel says that after Christopher Street:
“A moment later there was a slight lurch, and those in the train knew that they had rounded the curve at Morton Street and were pointing straight for the Hudson.”