A relic of the old elevated subway days, Sedgwick Ave station connected the Jerome Ave line (4 train) to the 9th Ave Elevated. This was the connection between the old Polo Grounds and Yankee Stadium, the origin of the term “subway series”. The elevated were torn down over 50 years ago and very little remain.
The station was built to allow transfer from the IRT 9th Ave elevated line to the New York Central RR (predecessor to Metro North) Putnam Line. The station is built into the side of a cliff and a tunnel was blasted through the ridge to a station at Jerome Ave behind the old Yankee Stadium. From here the line rose to connect with the elevated IRT Jerome Ave Line (4 Train). If you take the train past Yankee Stadium you’ll see where the three tracks spread open for a stretch for no apparent reason. This is where the 9th Ave el connected to the Jerome Ave el.
This service was shut down after the 9th Ave el was demolished and the Putnam Line discontinued. Even the ROW is gone, now located somewhere under the new Yankee Stadium’s left outfield. The roof of the station is actually the Major Deegan Expressway.
I explored this station with a couple of trusted friends and it was the first time I have encountered a homeless person living underground (the so called Mole People of myth). Once he realized we weren’t there to harass him he was very friendly and let us take pictures. We talked with him and gave him some food for his troubles. We weren’t just exploring some abandoned place, we where in his home so we were respectful. He told us about tunnels that were further within the station but we would have had to crawl through lots of garbage and probably dead rats so we passed.