(MCT) — LOS ANGELES — Civil War veteran William Hood arrived at the mosquito-infested swamps near Bakersfield in 1874 to build a rail line that would soar through the Tehachapi Mountains, linking the Bay Area and Southern California for the first time.

Hood, Southern Pacific Railroad’s chief assistant engineer, assembled 3,000 Chinese immigrants with picks, shovels and dynamite. They snaked the track up treacherous mountain ridges, twisted it back and forth around canyons and punched it through sheer rock in a series of 18 tunnels — climbing 4,025 vertical feet along the way.