Union Pacific Rail Road

Union Pacific Railroad

System map (trackage rights in purple)
General Electric ET44AH locomotive photographed in June 2016
Reporting mark	UP (road locomotives), UPY (yard locomotives), UPP (passenger railcars)
Locale	United States from Chicago, Illinois, and cities along the Mississippi River to the Pacific coast
Dates of operation	1862–present (legacy) First (original) company, Union Pacific Rail Road: 1862-1880 Second company, Union Pacific Railway: 1880-1897 Third company, Union Pacific Railroad (Mark I): 1897-1998 Fourth company, Union Pacific Railroad (Mark II): 1969-present (the fourth company began as the Southern Pacific Transportation Company, the last incarnation of the Southern Pacific railroad which lasted from 1969-1998; became the fourth Union Pacific railroad in 1998 during the UP-SP merger)
Track gauge	4 ft 8 1⁄2 in (1,435 mm)
Length	32,100 miles (51,660 km)
Headquarters	1400 Douglas Street Omaha, Nebraska
Website	www.up.com

1862–present (legacy)

The Union Pacific Railroad (reporting mark UP) (or Union Pacific Railroad Company and simply Union Pacific) is a freight hauling railroad that operates 8,500 locomotives over 32,100 route-miles in 23 states west of Chicago and New Orleans. The Union Pacific Railroad system is the second largest in the United States after BNSF Railway and it is one of the world's largest transportation companies. The Union Pacific Railroad is the principal operating company of the Union Pacific Corporation (: UNP); both are headquartered in Omaha, Nebraska.

The Union Pacific legacy began in 1862 with the original company, called the Union Pacific Rail Road, which was part of the First Transcontinental Railroad project, later known as the Overland Route. Two more Union Pacific railroads were formed after that, the Union Pacific Railway (the second company) which absorbed the original company in 1880 and the Union Pacific "Railroad" (the third company) which absorbed the Union Pacific Railway in 1897-1898.

The third incarnation of the Union Pacific Railroad which operated from 1897 to 1998 is referred to as Mark I and it makes up the bulk of the Union Pacific history. The third incarnation of the Union Pacific Railroad produced the well known Big Boy steam locomotives such as the Union Pacific 4014 and the Union Pacific 4012. Other well known steam locomotives were also produced by the third Union Pacific Railroad such as the Union Pacific 3985, the Union Pacific 3977, and the Union Pacific 844. The third incarnation of the Union Pacific Railroad also produced the Union Pacific 6936 diesel locomotive.