The Tehachapi Loop is a 0.73-mile (1.17 km) long spiral, or helix, on the Union Pacific Railroad Mojave Subdivision through Tehachapi Pass, of the Tehachapi Mountains in Kern County, south-central California. The line connects Bakersfield and the San Joaquin Valley to Mojave in the Mojave Desert. The line, which sees an average of almost 40 trains each day, is one of the busiest single-track mainlines in the world.
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