Far before passenger railroading operations and travel by train was even conceived, the United States, and the rest of the world, had little other means of moving people and goods than horse and watercraft (sailing ships, river boats, etc.) as steam power would not become available in our country until roughly sixty years after the signing of the Declaration of Independence. This was essentially the way things always were throughout human history and changed little until the 19th century.
However, all of this changed after 1804 when the first steam locomotive was built by Richard Trevithick and Andrew Vivian for the narrow gauge Penydarren Tramway in Wales and later first tested in America on the Baltimore & Ohio Railroad in 1829, now known famously as the Tom Thumb (while the locomotive actually lost the race with the horse [just barely!], it more than proved its ability as a reliable source of mechanical transportation). With this new technology, thus began the age of steam and a better, more efficient, means of transportation. Not only that but the steam locomotive was also a major driving force in settling America west of the Appalachian Mountains.
It was during the 1930s that lightweight materials, like aluminum, began to be used in car construction. Not only did this make the car lighter which was easier on the track structure (and less difficult for a locomotive to pull) but also streamlining became widely popular during this time and aluminum was light and flexible enough to be used as shrouding to streamline both cars and locomotives.
One of the first, and perhaps most famous streamlined trains was the Burlington’s Zephyr 9900 trainset, built in 1934. Sleek, fast, and comfortable (for instance, it broke the speed record for traveling between Denver and Chicago, covering the 1,000+ mile distance non-stop in only thirteen hours and five minutes) it paved the way for an entire generation of streamlined trains. Famous passenger trains to follow included names like the Milwaukee’s Hiawatha, the NYC’s 20th Century Limited, PRR’s Broadway Limited, and the Great Northern’s Empire Builder.
However, following WWII passenger traffic began to drop significantly and would not recover, even while some railroads began to update their passenger fleets with new equipment through the 1950s. A decade later, in the 1960s, industry losing significantly with its passenger operations (while passenger trains are rarely profitable, before the 1950s railroads were earning enough that their freight revenues could easily offset the losses) and desperately wanted out.
Relief would finally come in the way of the National Railroad Passenger Corporation, or Amtrak, which began operations on May 1st, 1971. Government-controlled and funded, Amtrak operates almost exclusively over the private freight railroads, save for the Northeast where it owns the [mostly] PRR’s former Northeast Corridor (NEC), a four-track main line operating between Washington, D.C. and Boston
The Union Pacific's M-10001 was the second streamliner built by the Union Pacific in 1934. The UP's first, the City of Salina was completed early in 1934 to be followed by this train, the City of Portland. It is similar to the M-10000 only twice as long. The new transcontinental streamliner consisted of three units similar to the M-10000 plus three Pullman sleeping cars. In October 1934 the City of Portland ran from Los Angeles to New York City (3,248 miles) in 56 hours and 55 minutes, the fastest transcontinental journey ever made by rail. At several points along the line she made up to 120 miles an hour. In the first week of May 1935, the train went into regular service between Chicago and Portland