CLASSIC TRACK DIAGRAMS
Former Pennsylvania Railroad main line Pittsburgh and Crestline, as it existed around the 1950's. The entire line has now been equipped with CTC at least since the 1990's, enabling elimination of manual interlocking towers. The portion between Pittsburgh and Alliance is now part of Norfolk Southern's main line between Pittsburgh and Chicago, which uses the former Pennsylvania Railroad line between Alliance and Cleveland, and the former New York Central main line west of Cleveland. Except for several miles of fourth track west of Pittsburgh, no trackage has been removed. The segment between Alliance and Crestline now has portions of single track. Previously that entire segment was at least double track, with some segments of third and fourth track until at least the 1950's. Where three or four tracks existed, the inner tracks were used by passenger trains, and the outer tracks were used by freight trains.