Union Pacific's History

Union Pacific and Central Pacific officials mark the inauguration of the transcontinental railroad with a presentation of ceremonial gold and silver spikes at Promontory Summit, Utah.

Union Pacific opens the first permanent bridge across the Missouri River between Omaha, Nebraska, and Council Bluffs, Iowa. The bridge has 11 spans, each 250 feet long and 60 feet above the water. 

Standard Time, proposed by the nation's railroads, is adopted throughout the U.S. In the eastern part of each time zone, there was a noon based upon sun-time and then another when clocks and watches were set back to the new standard railroad time.

Union Pacific is sold to a group of investors for $110 million. Their number includes E.H. Harriman, then-president of the Illinois Central, who spends the next decade reorganizing the company. 

Union Pacific and Southern Pacific create Pacific Fruit Express to ship perishable fruits from the West Coast. The initial order of 6,000 insulated refrigerator cars grew, by 1921, to 19,200 rail cars carrying 170,000 carloads.

During both World Wars, American railroads transport vast amounts of troops, military equipment and supplies from U.S. bases and factories to coastal ports. During World War I (1917-1918) alone, more than 100,000 new rail cars and almost 2,000 steam engines are requested to meet wartime demands.

The 6.21 mile-long Moffat Tunnel is completed in Colorado, allowing Denver & Salt Lake to abandon its route over Rollins Pass – shortening its route by 22.84 miles. 

Union Pacific opens the Sun Valley Resort in Idaho, the country's first western ski resort. It features the world’s first ski lift with chairs, invented by a Union Pacific mechanical engineer in Omaha.

The largest steam locomotive ever built, the Big Boy No. 4014, goes into service on Union Pacific lines. This same year, diesel power is introduced for freight service.

Union Pacific acquires Spokane International, giving the railroad a connection with Canadian Pacific Railway. 

As Union Pacific grew as a railroad, so did its non-rail business. The Union Pacific Corporation is established as a holding company, with Union Pacific Railroad as one of its operating companies. 

The National Rail Passenger Service Act transfers most passenger service in the U.S. to Amtrak. The federally subsidized railroad company serves nearly 30 million passengers each year. 

Union Pacific's Harriman Dispatching Center opens in Omaha, centralizing 10 regional dispatching centers from around the country in one location.

The Union Pacific-Southern Pacific merger takes effect, forming the largest railroad in the U.S. The new system covers 31,000 miles through 24 states and runs 2,000 trains a day. 

Union Pacific operates a special train – featuring two specially painted locomotives and a cauldron car – carrying the Olympic flame across 11 states over more than 3,200 miles enroute to the Winter Games in Salt Lake City, Utah. 

Photo Credit: Todd Warshaw/Pool/Getty Images

In recognition of the 150th anniversary of the completion of the transcontinental railroad, Union Pacific celebrates by sending Big Boy No. 4014 and the “Living Legend” No. 844 on a steam tour called "The Great Race to Ogden."

Union Pacific is the first Class I railroad to modernize the “big three” core operating platforms: Positive Train Control (PTC), Computer-Aided Dispatch (CADx) and Transportation Management (NetControl). The NetControl cutover unlocks real-time data Union Pacific leverages to optimize performance.