Planned by Theodore Judah, the Central Pacific Railroad was authorized by Congress in 1862. It was financed and built through "The Big Four '' (who called themselves "The Associates ''): Sacramento, California businessmen Leland Stanford, Collis Huntington, Charles Crocker, and Mark Hopkins. Crocker was in charge of construction. Construction crews comprised 12,000 Chinese emigrant workers by 1868, when they constituted eighty percent of the entire work force. They laid the first rails in 1863. The "Golden spike '', connecting the western railroad to the Union Pacific Railroad at Promontory, Utah, was hammered on May 10, 1869. Coast - to - coast train travel in eight days became possible, replacing months - long sea voyages and lengthy, hazardous travel by wagon trains.
where did the union pacific and central pacific railroads meet
at Promontory, Utah