The Tehachapi Loop is a long

spiral In mathematics, a spiral is a curve which emanates from a point, moving farther away as it revolves around the point. Helices Two major definitions of "spiral" in the American Heritage Dictionary are:helix A helix () is a shape like a corkscrew or spiral staircase. It is a type of smooth space curve with tangent lines at a constant angle to a fixed axis. Helices are important in biology, as the DNA molecule is formed as two intertwined helices, ...

, on the

Union Pacific Railroad The Union Pacific Railroad , legally Union Pacific Railroad Company and often called simply Union Pacific, is a freight-hauling railroad that operates 8,300 locomotives over routes in 23 U.S. states west of Chicago and New Orleans. Union Paci ...

Mojave Subdivision through

Tehachapi Pass Tehachapi Pass (Kawaiisu: ''Tihachipia'', meaning "hard climb") is a mountain pass crossing the Tehachapi Mountains in Kern County, California. Traditionally, the pass marks the northeast end of the Tehachapis and the south end of the Sierra Nev ...

, of the

Tehachapi Mountains The Tehachapi Mountains (; Kawaiisu: ''Tihachipia'', meaning "hard climb") are a mountain range in the Transverse Ranges system of California in the Western United States. The range extends for approximately in southern Kern County and northwest ...

Kern County Kern County is a county located in the U.S. state of California. As of the 2020 census, the population was 909,235. Its county seat is Bakersfield. Kern County comprises the Bakersfield, California, Metropolitan statistical area. The county sp ...

, south-central

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

. The line connects

Bakersfield Bakersfield is a city in Kern County, California, United States. It is the county seat and largest city of Kern County. The city covers about near the southern end of the San Joaquin Valley and the Central Valley region. Bakersfield's populat ...

and the

San Joaquin Valley The San Joaquin Valley ( ; es, Valle de San Joaquín) is the area of the Central Valley of the U.S. state of California that lies south of the Sacramento–San Joaquin River Delta and is drained by the San Joaquin River. It comprises seven c ...

to Mojave in the

Mojave Desert The Mojave Desert ( ; mov, Hayikwiir Mat'aar; es, Desierto de Mojave) is a desert in the rain shadow of the Sierra Nevada mountains in the Southwestern United States. It is named for the indigenous Mojave people. It is located primarily in ...

. Rising at a steady two-percent grade, the track gains in elevation and makes a diameter circle. Any train that is at least 3,800 feet (1,162 m) (approx. 56 60’(67'11") box cars) long passes over itself going around the loop. At the bottom of the loop, the track passes through Tunnel 9, the ninth tunnel built as the railroad was extended from Bakersfield. The line averages about 36 freight trains each day; passenger services such as

Amtrak The National Railroad Passenger Corporation, Trade name, doing business as Amtrak () , is the national Passenger train, passenger railroad company of the United States. It operates inter-city rail service in 46 of the 48 contiguous United Stat ...

's '' San Joaquin'' are banned from using the loop, while the ''

Coast Starlight The ''Coast Starlight'' is a passenger train operated by Amtrak on the West Coast of the United States between Seattle and Los Angeles via Portland and the San Francisco Bay Area. The train, which has operated continuously since Amtrak's formati ...

'' can only use it as a detour. Its frequent trains and scenic setting make the Tehachapi Loop popular with

railfan A railfan, rail buff or train buff (American English), railway enthusiast, railway buff or trainspotter (Australian/British English), or ferroequinologist is a person who is recreationally interested in trains and rail transport systems. Rail ...

s. In 1998, it was named a

National Historic Civil Engineering Landmark __NOTOC__ The following is a list of Historic Civil Engineering Landmarks as designated by the American Society of Civil Engineers since it began the program in 1964. The designation is granted to projects, structures, and sites in the United State ...

; it is also designated as

California Historical Landmark A California Historical Landmark (CHL) is a building, structure, site, or place in California that has been determined to have statewide historical landmark significance. Criteria Historical significance is determined by meeting at least one of ...

#508.

History

One of the engineering feats of its day, the Loop was built by

Southern Pacific Railroad The Southern Pacific (or Espee from the railroad initials- SP) was an American Class I railroad network that existed from 1865 to 1996 and operated largely in the Western United States. The system was operated by various companies under the ...

to ease the grade over Tehachapi Pass. Construction began in 1874, and the line opened in 1876. Contributors to the project's construction include

Arthur De Wint Foote Arthur De Wint Foote (1849–1933) was an American civil engineer and mining engineer who impacted the development of the American West with his innovative engineering works and entrepreneurial ventures. In Northern California in the late 1 ...

and the project's chief engineer, William Hood. The

siding Siding may refer to: * Siding (construction), the outer covering or cladding of a house * Siding (rail) A siding, in rail terminology, is a low-speed track section distinct from a running line or through route such as a main line, branch l ...

on the loop is known as Walong after Southern Pacific District Roadmaster W. A. Long. The project was constructed under the leadership of Southern Pacific's civil engineers, James R. Strobridge and William Hood, using a predominantly Chinese labor force. The Tehachapi line necessitated 18 tunnels, 10 bridges, and numerous water towers to replenish steam locomotives. Between 1875 and 1876 about 3,000 Chinese workers equipped with little more than hand tools, picks, shovels, horse-drawn carts and blasting powder cut through solid and decomposed granite to create the

helix A helix () is a shape like a corkscrew or spiral staircase. It is a type of smooth space curve with tangent lines at a constant angle to a fixed axis. Helices are important in biology, as the DNA molecule is formed as two intertwined helices, ...

-shaped loop with grades averaging about 2.2 percent and an elevation gain of . In 1882, the line was extended through Southern California and the Mojave Desert with 8,000 Chinese men working under Strobridge and another man. A large white cross, "The Cross at the Loop", stands atop the hill in the center of the loop in memory of two Southern Pacific Railroad employees killed on May 12, 1989, in a train derailment in

San Bernardino, California San Bernardino (; Spanish for "Saint Bernardino") is a city and county seat of San Bernardino County, California, United States. Located in the Inland Empire region of Southern California, the city had a population of 222,101 in the 2020 cen ...

. The Tehachapi Depot Museum is located in the nearby town of Tehachapi.

Operations

The Loop became the property of the

in 1996, when the Union Pacific and Southern Pacific systems merged. Trains of the

BNSF Railway BNSF Railway is one of the largest freight railroads in North America. One of seven North American Class I railroads, BNSF has 35,000 employees, of track in 28 states, and nearly 8,000 locomotives. It has three transcontinental routes that ...

also use the loop under

trackage rights Railway companies can interact with and control others in many ways. These relationships can be complicated by bankruptcies. Operating Often, when a railroad first opens, it is only a short spur of a main line. The owner of the spur line may con ...

. Although Southern Pacific ran passenger trains on the Loop for years, it banned passenger service there soon after handing its trains to

in 1971. Union Pacific has maintained the ban since taking over Southern Pacific. As a result, Amtrak's '' San Joaquin'' train is unable to directly serve Los Angeles. Amtrak operates

Thruway Motorcoach Amtrak Thruway is a system of through-ticketed transportation services to connect passengers with areas not served by Amtrak trains. In most cases these are dedicated motorcoach routes, but can also be non-dedicated intercity bus services, tran ...

buses for passengers wanting to travel between the Central Valley and Los Angeles. An exception is made for the ''

'', which uses the line as a detour if its

normal route A normal route or normal way (french: voie normale; german: Normalweg) is the most frequently used route for ascending and descending a mountain peak. It is usually the simplest route. Overview In the Alps, routes are classed in the following way ...

is closed.

California Historical Landmark

The California Historical Landmark plaque reads: :''NO. 508 TEHACHAPI LOOP - From this spot may be seen a portion of the world-renowned Loop completed in 1876 under the direction of William Hood, Southern Pacific railroad engineer. In gaining elevation around the central hill of the Loop, a 4,000-foot train will cross 77 feet above its rear cars in the tunnel below.'' The markers at the overlook were rearranged when a viewing platform was constructed at the scenic overlook on Woodford-Tehachapi Road in the summer of 2021. The cement platform was built so that railroad enthusiasts can view trains on the loop while keeping a safe distance from the winding, two-lane roadway.

References

External links

New aerial video of the 2nd track improvement, Nov 2016

Aerial video of 4000' train going uphill through the loop Nov 2015

Tehachapi Loop - A Brief History

Tehachapi Loop Photos

Photo Gallery of Tehachapi Loop shots

HO Scale Model
at the

San Diego Model Railroad Museum The San Diego Model Railroad Museum is a model railroad exhibit in San Diego, California. At 27,000 sq. ft., it is the largest such indoor exhibit in North America, and one of the largest in the world. The museum is located on the lower level of t ...

Stay In The Loop - Tehachapi News & Entertainment

Aerial video of BNSF train traversing Tehachapi Loop

{{Coord, 35, 12, 03, N, 118, 32, 13, W, format=dms, display=title, type:landmark_region:US-CA Rail infrastructure in California Southern Pacific Railroad Atchison, Topeka and Santa Fe Railway Transportation buildings and structures in Kern County, California California Historical Landmarks Historic Civil Engineering Landmarks Transport infrastructure completed in 1876 Tourist attractions in Kern County, California Tehachapi Mountains 1876 establishments in California Union Pacific Railroad lines

History

Operations

California Historical Landmark

See also

References

External links