Railyards were as far north as Oak Point Yard in The Bronx; all the way down to St. George in Staten Island.

A number of railroads had there own "Railroad Navy" as they were called. These navies included: Tugboats, Barges, Lighters, Carfloats, floating Grain Elevators, among many other highly specialized pieces of marine equipment.

Each of these railroads also interchanged cars by way of carfloating. In simplistic terms; what was done was:
a locomotive would push a cut of cars onto an apron or floatbridge. This apron was attached to a carfloat barge. This barge had tracks on it (usually three) and was basically a floating yard. The apron was the span from land to the barge. much like a floating bridge. The apron was a sturdy piece, either wood or steel. The apron was fixed on the land end, but the other end was moveable to deal with tides. Some were supported by pontoons on the water end or by an overhead gantry type lift. This gantry would take up the shock and the twisting and turning of the loading of the barge.

A major player in the NY Harbor Railroads were the small land locked terminal lines:

• Brooklyn Eastern District Terminal
• Bush Terminal
• Jay Street Connecting, and the
• New York Dock.

Later on, the railroads would be the New York Cross Harbor, which in turn became NYNJ Rail.

These small railroads were only accessible by means of carfloating, and they served offline terminals and a number of team tracks in that specific area, with no physical connections to a Class One railroad. The exception to this rule was the Bush Terminal Railroad, which was able to interchange with the Long Island Rail Road and New York, New Haven & Hartford RR at the 65th Street Yard interchange in Owl's Head, Brooklyn, NY.