Williams Loop
Encyclopedia
The Williams Loop is a rail spiral
located on the Union Pacific Railroad
's (originally Western Pacific Railroad
's) Feather River Route
through the Sierra Nevada Mountains in north eastern California
, connecting the Sacramento Valley
to Salt Lake City via the Feather River
valley. Located about ten miles east of East Quincy
, the loop is used to gain elevation on the WP's eastward climb to its summit
at Beckwourth Pass
while maintaining the railroad's overall 1.0 percent (compensated) grade, the least steep of any grade on a transcontinental railroad.
Spiral (railway)
A spiral is a technique employed by railways to ascend steep hills.A railway spiral rises on a steady curve until it has completed a loop, passing over itself as it gains height, allowing the railway to gain vertical elevation in a relatively short horizontal distance...
located on the Union Pacific Railroad
Union Pacific Railroad
The Union Pacific Railroad , headquartered in Omaha, Nebraska, is the largest railroad network in the United States. James R. Young is president, CEO and Chairman....
's (originally Western Pacific Railroad
Western Pacific Railroad
The Western Pacific Railroad was a Class I railroad in the United States. It was formed in 1903 as an attempt to break the near-monopoly the Southern Pacific Railroad had on rail service into northern California...
's) Feather River Route
Feather River Route
The Feather River Route is a rail line that was built and operated by the Western Pacific Railroad. It was constructed between 1906 and 1909, and connects the cities of Oakland, California, and Salt Lake City, Utah...
through the Sierra Nevada Mountains in north eastern California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
, connecting the Sacramento Valley
Sacramento Valley
The Sacramento Valley is the portion of the California Central Valley that lies to the north of the San Joaquin-Sacramento Delta in the U.S. state of California. It encompasses all or parts of ten counties.-Geography:...
to Salt Lake City via the Feather River
Feather River
The Feather River is the principal tributary of the Sacramento River, in the Sacramento Valley of Northern California. The river's main stem is about long. Its length to its most distant headwater tributary is about . Its drainage basin is about...
valley. Located about ten miles east of East Quincy
East Quincy, California
East Quincy is a census-designated place in Plumas County, California, United States. The population was 2,489 at the 2010 census, up from 2,398 at the 2000 census.-Geography:East Quincy is located at ....
, the loop is used to gain elevation on the WP's eastward climb to its summit
Route summit
A route summit is the highest point on a transportation route crossing higher ground. The term is often used in describing railway routes, less often in road transportation...
at Beckwourth Pass
Beckwourth Pass
Beckwourth Pass is the lowest Sierra Crest mountain pass and is located at the Sierra Valley's eastern edge near Chilcoot-Vinton, Plumas County, California. Beckwourth Pass is east of Beckwourth, California, in the Sierra Nevada, and is northwest of Reno, Nevada. The pass carries California State...
while maintaining the railroad's overall 1.0 percent (compensated) grade, the least steep of any grade on a transcontinental railroad.