Southern Pacific Lines

Southern Pacific Transportation Company

SP system map (before the 1988 DRGW merger)
Reporting mark	SP
Locale	Arizona, Arkansas, California, Colorado, Illinois, Kansas, Louisiana, Missouri, Nevada, New Mexico, Oklahoma, Oregon, Tennessee, Texas, Utah
Dates of operation	1865–1998 (legacy) Original incarnation was established in 1865 and the Southern Pacific legacy ended with the last incarnation in 1998; the last incarnation was established in 1969 and it is now the current incarnation of the Union Pacific Railroad
Predecessor	Central Pacific Railroad
Successor	Union Pacific Railroad (in name only) Some former SP tracks are now operated by BNSF Railway
Track gauge	4 ft 8 1⁄2 in (1,435 mm) standard gauge with some 3 ft (914 mm) gauge branches
Headquarters	San Francisco, California

1865–1998 (legacy)

The Southern Pacific (reporting mark SP) (or Espee from the railroad initials- SP) was a name of multiple American Class I railroads that existed from 1865 to 1998 and all operated in the Western United States. The names that represented the Southern Pacific were Southern Pacific Railroad, Southern Pacific Company and Southern Pacific Transportation Company.

The original Southern Pacific was founded as a land holding company in 1865, later acquiring the Central Pacific Railroad through leasing. By 1900, the Southern Pacific system was a major railroad system incorporating many smaller companies, such as the Texas and New Orleans Railroad and Morgan's Louisiana and Texas Railroad. It extended from New Orleans through Texas to El Paso, across New Mexico and through Tucson, to Los Angeles, through most of California, including San Francisco and Sacramento. Central Pacific lines extended east across Nevada to Ogden, Utah, and reached north through Oregon to Portland. Other subsidiaries eventually included the St. Louis Southwestern Railway (Cotton Belt), the Northwestern Pacific Railroad at 328 miles (528 km), the 1,331-mile (2,142 km) Southern Pacific Railroad of Mexico, and a variety of 3 ft (914 mm) narrow gauge routes. The SP was the defendant in the landmark 1886 United States Supreme Court case Santa Clara County v. Southern Pacific Railroad which is often interpreted as having established certain corporate rights under the Constitution of the United States. In 1929 SP/T&NO operated 13848 route-miles not including Cotton Belt, whose purchase of the Golden State Route circa 1980 nearly doubled its size to 3,085 miles (4,965 km), bringing total SP/SSW mileage to around 13,508 miles (21,739 km).