"Don't They Know East From West?"
In the Santa Clarita Valley, westbound trains don't really run in a geographically westward direction.
Often, they travel northwest or north. In Soledad Canyon, they run due east. In SoCal rail parlance, "westbound" means
"toward San Francisco." It's the same for eastbound trains, only in reverse, in the direction of Yuma. Click map to enlarge.
September 26, 1953 - Photo by Stan Kistler of Grass Valley, Calif., who describes it as "Southern Pacific Owl, Train No. 58, near Honby, California."
More specifically, this eastbound train (traveling west) has just left the area of Humphreys Station (out of frame to the right) and is approaching Sierra Highway, formerly US-6 (out of frame to the left), as
it heads toward Honby.
Location identification by Charles Mitchell, who says the house at upper left was the residence of Grace Nadeau and the "drainage ditch on the bottom is coming out of Nadeau Canyon" (pers. comm. 2017).