I would have to say that being a railfan in Manhattan is probably a bit different than what most fans in North America experience. I live on an island of only 22.96 square miles of area but I share that land with 1,626,159 of my neighbors. For you at home, that's 70,825.6 people for each of those 22.96 miles. That makes Manhattan the most densely populated county in the United States.
Most track in Manhattan is underground, is passenger, and off limits for obvious reasons. (It's just as well, for it is very hard to find pretty S curves with mountain scenery underground but I keep trying.) No freight train comes onto my island any more. Fact is, New York City as a whole gets 70% of it's freight by truck. And while Amtrak and Metro North run dual power locomotives by the dozens into Grand Central and Penn Station, there is exactly one diesel switcher on my island.
This one. And it doesn't move.
New York Central 8625 was never owned by that railroad. This loco, a 660-horsepower model S1 switcher was Alco order #74962 built in October 1946 as Erie RR 307 their Class SA-6b. It became Erie Lackawanna 307, Class SA-6, and sold as Brooklyn Eastern Terminal District No. 25 in November 1967. It became New York Cross Harbor No. 25 in August 1983 and worked until the 1990’s. In 2006, No. 25 was repainted in it's new garb and brought to the new Riverside Park South as a memorial to the railroad whose freight yard here made this housing development and park possible. A rueful railfan note: all land visible in this shot was once covered with track and hundreds of freight cars. There was even a roundhouse.
So if I ever get a hankering for diesel switcher action (pretend) in Manhattan, I know where I can go.