The Central Pacific Railroad was established in 1861 by the “Big Four”—Leland Standford, Collis P. Huntingon, Charles Crocker, and Mark Hopkins. The Central Pacific was part of the first transcontinental rail line, though its progress was often slow. Chinese immigrants were largely responsible for building the rail, which began in Sacramento, California, and reached east until it met the Union Pacific Railroad in Promontory Summit, Utah, in May 1869 to complete the transcontinental line.