Unless you’re a railroad enthusiast, engineer, or California history buff, you may not know about this engineering marvel in Southern California known as “one of the seven wonders of the railroad world.” The Tehachapi Loop is a 3,779 foot spiral in the Tehachapi Mountains, constructed in 1876 to help trains gain elevation gradually at a 2.2% grade. Keep reading to learn more about this lesser-known technical masterpiece in California.
History and design of the Tehachapi Loop
The Southern Pacific Railroad constructed the Tehachapi Loop between 1874-1876 as a crucial part of the first railroad line connecting San Francisco and Los Angeles. Chief engineer William Hood and civil engineer James R. Strobridge led the project with help from civil engineer Arthur De Wint Foote. Over 3,000 Chinese laborers worked with hand tools, picks, shovels, horse-drawn carts, and blasting powder to create the loop.
Trains use the loop to ascend the steep Tehachapi Pass, rising a total of 77 feet at a steady 2.2% grade around the 3,779-foot circle. Any train longer than 3,800 feet will pass over itself as it goes around the loop, making for some fascinating sights from the nearby viewing area.
Renowned for its engineering and historical significance, the Tehachapi Loop was designated as California Historical Landmark #508 in 1953, and as a National Historic Civil Engineering Landmark in 1998.
What’s more, you can watch trains traverse the Tehachapi Train Loop on a live stream! Check it out below.
Modern significance and operations
The Tehachapi Loop is found on the Union Pacific Railroad Mojave Subdivision, which connects Bakersfield and the San Joaquin Valley to Mojave in the Mojave Desert. Both the Union Pacific Railroad and the BNSF Railway use the loop, making it one of the busiest single-track mainlines in the country, with about 36-50 freight trains passing through it per day. While passenger trains haven’t used the loop since the ’70s, the Coast Starlight may use it as a detour when necessary.
Railroad enthusiasts and visitors are known to visit the site at a designated viewing area along Woodford-Tehachapi Road, about 4 miles from the Keene exit off Highway 58. The viewing spot is marked with two monuments commemorating the loop’s landmark status and has a few trails and picnic areas with different vantage points.
The nearby town of Tehachapi has a free railroad museum at the restored depot, dedicated to the history of the loop and the town’s rich railroad history. In fact, the Union Pacific Railroad recently designated Tehachapi as “Train Town USA,” and it makes for a fun road trip stop for railroad fans and local history lovers.
🌐 Learn more: Tehachapi Depot Railroad Museum