The Los Angeles and Salt Lake Railroad was a rail company in California, Nevada, and Utah in the United States, 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 Cima, Caliente, Sharp, and Lynndyl Subdivisions.

William Andrews Clark Sr. was an American entrepreneur, involved with mining, banking, and railroads, as well as a politician.