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Southern Pacific Railroad Semaphore Signals east of Tucson, AZ

Southern Pacific Railroad semaphore signal east of Tucson, AZ SP Railroad semaphore signal east of Vail, Arizona Southern Pacific Railroad semaphore signal east of Tucson, AZ

The original Southern Pacific track is used by eastward trains and the El Paso Southwestern track is used by westward trains. The tracks split near Wilmot but remain fairly close together until just after Vail. Then the SP line drops down to follow the river and the EPSW takes the highroad to avoid all the twist and turns near the river. The EPSW route was better engineered and has a lot fewer curves. A carryover from the 20s was the old semaphore signals used on both lines. CTC was added to the single track portions of the Sunset Route in the late 50s. Disk 56