(PD) Photo: Schumacher Portraits John Diedrich Spreckels, "The Great Builder," in 1901.
(PD) Image: San Diego Union The front page of the December 14, 1906 edition of the San Diego Union proclaims, "RAILROAD FROM SAN DIEGO TO YUMA IS NOW ASSURED."
(PD) Photo: John R. Signor Collection The construction camp at Valle Redondo, January 31, 1912.
(PD) Photo: Unknown An SDA survey party, August 1914.
(PD) Photo: Unknown Looking into the United States through Tunnel #4, 598 feet long.
(PD) Photo: Unknown SD&A gasoline-electric motor car No. 41, one of three similar self-propelled units used on commuter runs to La Mesa and Lakeside until they were retired in 1934.
(PD) Photo: Unknown The upper Campo Creek Viaduct, nearly 600 feet (183 meters) long, as it appeared on October 5, 1919.
(PD) Photo: Ralph P. Stineman Locomotive No. 50 of the San Diego and Arizona Rail line stands at a siding.
(PD) Photo: Ralph P. Stineman A San Diego and Arizona train takes a tour group over a newly constructed bridge and track section.
(PD) Photo: Unknown SD&A No. 25 and train have just emerged from Tunnel #16 westbound.
(PD) Drawing: San Diego and Arizona Railway Lines of the San Diego and Arizona Railway in California, and the Tijuana and Tecate Railway in Mexico.