This may be a reference to William Barstow Strong, the former president of the real world Atchison, Topeka and Santa Fe Railway. The prisoners at the NCRCF say that they were repairing and building railroads before the broke out, and rails in miraculously good condition seem to.

The locomotive at the entrance to Boulder City is adorned with the logo for the fictional Barstow Express.

I also added a few more trains to the tracks to fill it out a bit more and make the areas around them feel a bit different.

The locomotives are similar in appearance to the real world F-unit series of locomotives. Just felt like 'HEY Look at this cool train we made :D' I made it look like the Fallout New Vegas one and replaced all the default trains.

Locomotives appear only in Fallout: New Vegas.

One can be found in the rail yard at Callville Bay.

One is attached to several boxcars in the Gypsum train yard.

A lone engine sits on the tracks at the Boulder City train station.Locomotives are mentioned to still have functioned shortly after the Great War in the Capital Wasteland, utilized by the Settlers to leave the region from Union Station.

However, should the infestation be eradicated, the bartender of Boulder City will mention the trains will become operational once more. Traffic has been halted due to the deathclaw infestation, but Chomps Lewis in Sloan will tell the Courier that what they dig from their quarry is shipped off by train to the New Vegas Strip and other parts of the Mojave Wasteland. By 2281, the New California Republic has refurbished rail lines and uses these to move cargo and people across its territories, including the Mojave Wasteland. Railroads were used for transporting freight in the pre-War United States, used by locomotives of several different companies such as Barstow Express.

Fallout new vegas train