Timeline of the Southern Pacific Jawbone Branch:
1910–1912 – Survey and planning begin for a rail line to support the construction of the Los Angeles Aqueduct.
1912–1914 – Construction of the Jawbone Branch (also called the Lone Pine Branch) by the Southern Pacific Railroad. It runs from Mojave to Owenyo, about 90 miles.
1914–1920s – Line supports agriculture, mining, and the cement industry; connects with the narrow-gauge Carson & Colorado at Owenyo.
1930s–1940s – Steam locomotives dominate operations; regular mixed freight runs continue, including to and from Trona and Inyokern.
1950s–1960s – Diesel locomotives gradually replace steam. Traffic declines but continues, with some military use near Inyokern.
1970s – Operations decrease; the northern end of the line sees fewer trains.
1982 – A fire damages Tunnel #1 near Searles. The northern section from Searles to Lone Pine is shut down.
1990s – Rails removed north of Searles.
2000s–present – Southern portion near Trona still used by Trona Railway. Most of the branch is abandoned, but it is still traceable by grade and remnants.