Harlem Line is a century-old, 82 mile, five county & 38 station route between Grand Central Terminal in Midtown Manhattan, NYC to Wassiac in Dutchess County. Full electrical route just below Southeast & above that station is non-electricfied. It was part of the NY Central Railroad then renaming the Harlem Division in 1983. The diesel trains usually run as a shuttle on the northern end of the line, except for rush-hour express trains in the peak direction (two (morning) to/from (evening) Grand Central). With 38 stations, the Harlem Line has the most of any Metro-North main line. Its northern terminal, Wassaic, is the northernmost station in the system. It is the only Metro-North line used exclusively by that carrier (no use by Amtrak, though CSX services freight customers as far north as Mount Vernon) and the only one that uses the entirety of existing track. It is colored blue on Metro-North timetables and system maps, and stations on the line have blue trim. The blue color-coding appears to have started with timetables issued by predecessor New York Central for the then-Harlem Division as far back as 1965. The rolling stock (currently): M3A & M7A [electrical trains], PC32AC-DM (GE Genesis), some Siemens Charger locos & Shoreliner [cab car]. Try that route between GCT & North White Plains or Southeast with local, semi, original & super express services. Metro-North train #645 leaves White Plains en route to Southeast. For more info, go to... https://wikipedia.org/wiki/Harlem_Line https://wikipedia.org/wiki/New_York_Central_Railroad https://wikipedia.org/wiki/M1/M3_(railcar) https://wikipedia.org/wiki/M7_(railcar) https://wikipedia.org/wiki/GE_Genesis https://wikipedia.org/wiki/Siemens_Charger https://mta.info/schedules/metro-north/harlem
DTG, the owners of TSC are not making any content for the game. Third party creators are still building add-ons for the game and there is a lot of freeware. If you want something like this you might be best asking on the TSW forums https://forums.dovetailgames.com/forums/suggestions.75/
Even though they mostly only seem to care more about freight routes. So I'm not hopeful that they will ever do it anyway. Also, there is a Harlem Route on the workshop, which is okay for what it is. But it is much longer than DTG would ever bother to do these days, if they still cared enough about TSC. Not sure why redirect him to a TSW forum, which he may not even care for (understandably so). Also, they've already done a fraction of the route. I wouldn't be quick to propose a route for sim they seem to habitually cheap out on, regarding American Content.