The Berlin S Bahn's S1 is a pink color, 86 minute & 35 station route started in May 1st, 1985 between Wannsee [south side] & Oranienburg [north side]. Operations The southern end of the line is at Wannsee, on the Wannsee Railway. Trains run north over that line to Anhalter Bahnhof where they enter the Berlin Nord-Süd Tunnel, exiting at Berlin Nordbahnhof. Between Berlin Nordbahnhof & Bornholmer Straße trains use the Berlin-Szczecin railway. Finally, trains use the southern end of the Berlin Northern Railway between Bornholmer Straße & Oranienburg. As of the December 2023 timetable change, the S1 operates every 10 minutes between Wannsee & Frohnau, and every 20 minutes between Frohnau & Oranienburg. Since becoming a numbered route in 1984, the S1's line color is pink. This route also features S25/S26 between Gesundbrunnen, Schonholz & Yorckstr, as well as S85 between Bornholmer Str & Frohnau. Service history The S1 was created along with the S2 & S3 on January 9th, 1984, when the Berliner Verkehrsbetriebe (BVG) took over the S-Bahn network from the East German Deutsche Reichsbahn in West Berlin: however, the dilapidated state of the West Berlin network at the time meant that the first S1 trains did not run until May 1st, 1985, when the line between Wannsee and Anhalter Bahnhof reopened. In 1990, the S1 was extended to Frohnau while the S2 was curtailed to Gesundbrunnen. It was extended to its present northern terminus of Oranienburg on May 31st, 1992, after the reopening of the Berlin Northern Railway between Frohnau & Hohen Neuendorf. A DB Class 481 on line S1 towards Oranienburg on its arrival at Schönholz station. For more info, go to... https://sbahn.berlin/en/plan-a-journey/s1/ https://wikipedia.org/wiki/S1_(Berlin) https://wikipedia.org/wiki/S25_(Berlin) https://wikipedia.org/wiki/S26_(Berlin) https://wikipedia.org/wiki/S85_(Berlin) https://wikipedia.org/wiki/DBAG_Class_481 https://sbahn.berlin/fileadmin/user_upload/Linien/Regelfahrplaene/Fahrplan-S1.pdf
I did suggest that route well not actually but I did suggest something similar to that, it was a s bahn route, here it is down below https://forums.dovetailgames.com/threads/ringbahn-berlin-circle.90308/#post-981305