Tehachapi Pass, Rail mountain pass in Kern County, California, US

Tehachapi Pass crosses the Tehachapi Mountains in Kern County, California, traditionally marking the northeast end of the Tehachapis and the south end of the Sierra Nevada. The narrowest part of the canyon on the eastern approach sits at about 3,771 feet (1,149 m), while the actual high point, signed as Tehachapi Summit, lies just east of the town of Tehachapi at 4,031 feet (1,229 m) beside the railroad and Tehachapi Boulevard. State Route 58 and the Union Pacific–BNSF Mojave Subdivision both run through the pass.

The Southern Pacific Railroad built the railway through this pass in 1876, creating a direct connection between Central California and the Mojave region. This construction transformed freight movement and settlement patterns across southern California.

The Kitanemuk people developed trade pathways across this mountain pass, establishing it as a crossroads between different communities. These early routes shaped how people still move through the landscape today.

State Route 58 remains open year-round, though winter weather can occasionally affect conditions, so checking forecasts before traveling is wise. Several pullouts along the road offer good spots to stop and take in the views.

The Tehachapi Loop lies about 18 miles (29 km) west of the summit, on the rail line through the pass. There, longer trains climb in a spiral and cross over their own length. The loop is a landmark of the route opened by the Southern Pacific in 1876, now shared by Union Pacific and BNSF.