Tom,
Yes, that's the Harlem River with what we called the 138th St RR bridge in the background and the Willis Ave (or maybe the 3rd Ave?) vehicular bridge in front of it. I think the official name of the lift bridge was the Madison Ave Bridge. It carried trains from the Mott Haven area to Manhattan and toward Grand Central.
The low white building just beyond the traveling crane was the famous circular CNJ freight terminal with its intricate track work encircling the building. I think there are more photos of it somewhere on a previous page of this thread. It's an area I wish I had explored back in the day while it was still in operation.
Jim
