This John Ford-directed western once again reunited him with John Wayne and features some train footage mixed in. 

An early titles shot shows the narrow gauge steam train crossing Owens Valley in eastern CA. 

We next catch a glimpse of the train passing through town. Even though it's supposed to be the same train, this is a much older standard-gauge 2-8-0 with a wooden cab that looks nothing like the shots of the other engine. That's because this is Virginia & Truckee's #25 and three RKO-owned coaches on RKO's Encino Ranch backlot in Los Angeles (which sadly no longer exists).

V&T #25 is alive and well and operates during summer weekends around the loop at Nevada State RR Museum in Carson City. 

The other shots we see of the train actually in Owens Valley (even though it's supposed to be Arizona) are actually Southern Pacific's narrow-gauge #9. Today this engine is on display at nearby Laws Railroad Museum, awaiting inspection for a possible restoration. Even better news? It's sister engine SP #18 "The Slim Princess" is still operational and occasionally fires up in Laws and elsewhere. 

The nearly-identical SP #18 at the Great Western Steam Up in Carson City in 2022. 

More footage of the Southern Pacific engine on location. 

After crossing the dry lake in Death Valley, John Wayne is seen carrying the baby up to a high bluff overlooking the whole valley. Look familiar? This is Dante's View in Death Valley National Park - the exact same spot where Luke Skywalker and friends look out over Mos Eisley spaceport in "Star Wars."

The final scene of the film takes place back at Encino Ranch's western town as Robert is whisked off to Yuma jail. V&T #25 steams away with a combination baggage-passenger car that I believe is the old Northwestern Pacific RR #37, built in 1888 and bought by RKO in 1939. It has since been bought by Virginia & Truckee and renumbered #25. 

I believe this same car is being used for storage near the depot in Virginia City, NV today.