thumb|right|250px|Mappa delle linee nel 1930
'''Western Pacific Railroad''' è stata una compagnia americana operativa negli stati dell Union Pacific.
La linea principale della WP collegava Sacramento, Stockton e Oakland; da questa linea principale si staccavano 3 linee secondarie: due nello stato della Califorina (Keddie-Bieber e Niles-San Jose) e una nel Nevada (Reno Junction-Reno).

==Treni Passeggeri==
La WP operava alcuni tra i più prestigiosi treni passeggeri degli Stati Uniti tra i quali spicca il leggendario ''California Zephyr'' (gestito congiuntamente da WP-Chicago Burlington & Quincy-Denver & Rio Grande Western.) che collegava Chicago con Oakland attraverso gli spettacolari scenari del Canyon del fiume Feather e le Montagne Rocciose. Sulla stessa tratta viaggiava anche il meno noto ''Exposition Flyer'' e lo ''Zephyrette'', questo ultimo limitato tra Salt Lake City e Oakland e operato da una singola automotrice tipo Budd.
Il ''Royal Gorge'' e lo ''Scenic Limited'' collegavano Oakland e St.Louis e vennero sospesi nel 1967, prima dell'avvento dell'Amtrak.

{{Infobox SG rail|
railroad_name=Western Pacific Railroad|
logo_filename=Western Pacific Railroad logo, color.jpg|
logo_size=151|
old_gauge=|
marks=WP|
locale=California, Nevada, and Utah|
start_year=1903|
end_year=1983|
successor_line=Union Pacific|
hq_city=San Francisco, California
}}
thumb|300px|right|"[[Drumhead (sign)|Drumhead" logos such as these often adorned the ends of observation cars on the '''Western Pacific Railroad'''.]]
The '''Western Pacific Railroad'''  was a Class I railroad in the United States. It is now part of the Union Pacific Railroad (UP). It was the second railroad company to use this name.  The original Western Pacific Railroad was established in 1865 to build the western-most portion of the Transcontinental Railroad between San Jose, California, and Sacramento, California.  This company was absorbed into the Central Pacific Railroad in 1870.

==History==
Founded in 1903, the '''Western Pacific Railroad''' was built as a portion of the Gould family's efforts to create a transcontinental railroad in the late 19th and early 20th century. 

One of the American West’s most popular railroads, the WP attracted rail enthusiasts from around the world. From 1910 to 1982, its diverse route provided scenic views of the San Francisco Bay Area, the mountain communities of the famous Feather River Route, and the deserts of Nevada and Utah. The Western Pacific originated in 1900 as the Alameda and San Joaquin Railroad. The railroad which would become the Western Pacific was financed and built by the
Pacific Coast. In 1909, it became the last railroad completed into California.

In 1931, WP opened a second mainline north out of the Feather River Canyon to reach the Great Northern Railway in northern California.  This route, called the "Highline", joined the Oakland to Salt Lake City mainline at a junction known as the triangle of intersecting track. 

thumb|300px|left|A 1930 map of the Western Pacific and [[Denver and Rio Grande Western Railroad systems.]]
One of the more well-known aspects of the Western Pacific was its operation of the ''California Zephyr'' passenger train, in conjunction with the Denver and Rio Grande Western Railroad and the Chicago, Burlington and Quincy Railroad.  The WP handled the "Silver Lady" from Oakland, California, to Salt Lake City, Utah.

Since it competed directly with the long-entrenched and much larger diesels, then kept some of these early diesels running in regular service long after they had been retired elsewhere.  It embraced computerized dispatching, concrete crossties and innovative equipment to protect customer shipments, at the same time fielding antique wooden cabooses and rebuilding outmoded freight cars.

thumb|300px|right|Western Pacific #581, a [[Baldwin Locomotive Works VO-1000, is seen in a September, 1945 builder's photo.]]
The Western Pacific owned several connecting short-line railroads.  The largest and most well-known was the Sacramento Northern Railway, which at one time reached from San Francisco to Chico, California. Others included the Tidewater Southern Railway, the Central California Traction, the Indian Valley Railroad and the Deep Creek Railroad.