A westbound Union Pacific train descends Cajon Pass behind UP C30-7 2449, SD40-2 3377 and another SD40-2 on its way to Los Angeles. This piggyback train is traveling on the original 1885-built line over Cajon Pass, constructed by Atchison Topeka & Santa Fe predecessor California Southern Railroad (later merged into the Southern California Railway). Union Pacific was granted trackage rights on the Southern California Railway in 1905, four years before the CSR was absorbed into the AT&SF. (Cajon Pass, California – January 21, 1984)