First transcontinental railroad completed at Promontory Summit

Background. The first transcontinental railroad, originally known as the Pacific Railroad, was a continuous line built between 1863 and 1869. It connected the eastern U.S. rail network at Council Bluffs, Iowa, with the Pacific coast at San Francisco Bay. The Central Pacific broke ground on January 8, 1863, and the Union Pacific reached the railroad town of Cheyenne in December 1867, having laid about 270 miles that year.

The Golden Spike Ceremony. On May 10, 1869, Leland Stanford, President of the Central Pacific Railroad, ceremonially tapped the gold 'Last Spike' with a silver hammer at Promontory Summit. This action connected the Central Pacific from Sacramento and the Union Pacific from Omaha. Many Chinese workers, who contributed significantly to the construction, were absent from the ceremony.

Scope and Limitations. The completion at Promontory Summit marked the joining of the Central Pacific and Union Pacific lines but did not constitute a seamless coast-to-coast rail network. Neither Sacramento nor Omaha were seaports with direct rail connections at the time. The official completion date for the Pacific Railroad as defined by the Pacific Railroad Act was determined to be November 6, 1869.