The UP Gila Sub is the ex-Southern Pacific Sunset Route that runs 255 miles from Yuma, AZ, to Tuscon, AZ. UP is slowly getting ready thru PTC upgrades or double tracking projects to replace any remaining ex-SP searchlight signals along this route. Roughly only 85 miles of original SP trackage is left with old signals along the Gila.
Between Dome and Wellton, there is 16 miles of original SP double track. The original main built by the end 1879, and the 2nd track was built in 1926. With the Gila Mountains looming in the background in the Dome Valley, this 1x1 eastbound auto train from Mira Loma, CA, bound for Nogales, AZ, (Mexico Border) rolls out of Dome heading east near MP 756, 20 miles east of Yuma. The train is running on Main #1 out of Dome around MofW working on a bridge, which is nontraditional for this section of double track.