San Pedro, Los Angeles and Salt Lake Railroad

The Los Angeles and Salt Lake Railroad (reporting mark SLR) was a rail company that completed and operated a railway line between its namesake cities, via Las Vegas, Nevada. Incorporated in Utah in 1901 as the San Pedro, Los Angeles and Salt Lake Railroad, the line was largely the brainchild of William Andrews Clark, a Montana mining baron and United States Senator. Clark enlisted the help of Utah's U.S. Senator Thomas Kearns, mining magnate and newspaper man, to ensure the success of the line through Utah. Construction of the railroad's main line was completed in 1905. Company shareholders adopted the LA&SL name in 1916. The railway was also known by its official nickname, "The Salt Lake Route", and was sometimes informally referred to as "The Clark Road". The tracks are still in use by the modern Union Pacific Railroad, as the Caliente, Sharp, and Lynndyl Subdivisions.

The development of the railway line that became the LA&SL began in 1871 when the Utah Southern Railroad began laying track southward from Salt Lake City. The Utah Southern, controlled by the much larger Union Pacific Railroad (UP), built a line to a station known as Juab, Utah, in 1879. From there a second UP subsidiary known as the Utah Southern Railroad Extension took up the work, completing trackage as far as Milford, Utah, in 1880. By the end of the century, these and other lines had been absorbed into the Oregon Short Line Railroad, a far larger UP subsidiary.

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