Can't help on the topography, but an Official Guide from December 1950 shows the New York Mail, out of Buffalo at 5.45 pm, with a sleeper for New York and a Buffet Lounge car for Elmira (9.29 pm), stopping at Lancaster, East Bethany, B. & O. Junction, Mount Morris, Groveland, Dansville, Wayland, Atlanta, Cohocton, Avoca, Bath, Campbell, Corning, and onward to Hoboken, where it arrived at 5.30 am, although the sleeper could be occupied until 8.00 (in 1945 it also made Kanona and Savona, but they were gone by 1950). Corresponding westbound service was provided by The Owl, leaving Hoboken at 1.05 am (sleeper for Elmira available for occupancy from 9.30 pm, arriving in Elmira at 8.55 am, when passengers for points beyond would move up to a coach). A Diner Lounge car was added at Binghamton. Other than that, the only stops made by other trains were Mount Morris, Dansville, Bath, and Corning. Darien Center and Alden were on the Erie, which roughly paralleled the DL&W as far as Lancaster, but then headed more southerly via Town Line, Marilla, Alden, Darien Center, Attica, Linden, Dale, Warsaw, Rock Glen, Silver Springs, Castile, Portage (Letchworth Park), Washington Hunt, and so on to Hornell, where it joined the Erie main line. The Erie used to have 3 trains a day via that route to and from Jersey City, but by 1950 it was down to one a day in each direction, and the eastbound, which left Buffalo at 5.10 pm, had no Jersey City connection unless you wanted to wait from 8.20 until midnight for The Lake Cities.