Bluelinec4 treated us, above, to some photos from Weehawken NJ. The line he shows ran alongside the road down the hill to the West Shre RR (NYC) terminal, which was a very busy place in the 40's when I grew up in that area. Many steam-powered commuter trains came there daily through a tunnel under 48th & 49th streets in Union City. After getting off the trains, commuters took the steam powered NYC ferries to 42nd St NYC, where they ran across the street to the trolley lines that ended across the street from the terminal. Some ferries from that Weehawken terminal also ran to Courtland St in lower NYC.
In the 40's, the trolley line ran west on 48th Street to Bergenline Ave, then south along the one-way street. Northbound cars used New York Avenue.
In the 30's, a line branched off 48th street and headed north, partly in a closed ROW and partly on Palisade Avenue, then through North Hudson Park. It crossed the lake in N.H. Park on a viaduct (I have a short movie of this my parents took when filming in the Park), and then ran north along a dedicated ROW. I beleive it went to Palisades Amusement Park and met with another line from the west. In the 40s and 50s, all these ROWs were still there.