On June 20, 1879, the Santa Fe Railway received a land grant from the Mexican government that allowed them to extend their reach through the valley of Sonora through to the coastal town of Guaymas on the Gulf of California.

[16]: 14  The Sonora Railway (an operating subsidiary) allowed the Santa Fe to effectively compete with the Southern Pacific Railroad for business on the West Coast of the United States.

The T&P had a significant foothold in Texas by the mid-1880s but construction difficulties delayed westward progress until American financier Jay Gould acquired an interest in the railroad in 1879.

In the wake of this setback, the Santa Fe was approached by the Citizens Railroad Committee of San Diego, who had formed a syndicate for the purpose of building a rail line to connect with the A&P in eastern California.

As of January 12, 1882, the California Southern commenced regular passenger and freight service between its National City terminus and Fallbrook Junction, just north of Oceanside.

The California Southern's attempts to cross over the SP tracks a year later led to a frog war that ended on August 11, 1883, with a court order in the CSRR's favor.

A real estate boom in the spring of 1887 brought thousands of people to Southern California, many of them traveling on "The Santa Fé Route" to San Diego.

[21] Recurring washouts in Temecula Canyon, however, often disrupted service; in response, the Santa Fe began construction of its 126-mile (203 km)-long "Surf Line" between Los Angeles' La Grande Station and the National City depot.

To that end, the City decided to stage an international exposition in celebration of the opening of the Canal, and to tout San Diego as the first U.S. port for ships traveling north after passing through the facility.

But San Diego, even with its natural landlocked harbor, was 100 miles (161 km) farther south than Los Angeles, which translated into an additional day of travel for both freight and passenger trains; in order for Santa Fe to compete with the Southern Pacific Railroad, the company needed a port closer to its rival's transcontinental terminus.

Santa Fe transferred most of its engine terminal yard to San Bernardino in 1887, then established an interim port facility in Redondo Beach the following year.

[17]: 45 Though the elegant California Southern depot had served San Diego for nearly three decades, the station was not adequate to handle the expected flood of visitors through the "Silver Gate" in 1915.

Construction began on a site just east of the existing structure on January 15, 1914, and was completed on December 31, at a total cost of $300,000 (equivalent to $9.13 million in 2023 adjusted for inflation).

[23]: 80  In 1936 the Santa Fe ordered a six-car trainset from the Budd Company specifically for the initiation of a new, streamlined named train between the Los Angeles Union Passenger Terminal and San Diego.

The United States' entry into World War II saw a significant increase in rail traffic to and from San Diego, both in the form of troop movements and transport of military vehicles and supplies.

[24] While freight shipments dropped precipitously after the War, passenger demand remained high, and traffic on the "Surf Line" ran second only to the Pennsylvania Railroad's New York–Philadelphia corridor.

[25] Passenger service on the San Diego and Arizona Eastern Railway (a successor to the SD&A) ended on January 11, 1951, due to years of continued declining patronage.

After more than sixty years of service, the San Diegan was rebranded as the Pacific Surfliner, reflecting extensions of the route over the past two decades to the Central Coast.

[28] The massive arch of the front entrance is flanked by twin campaniles, each topped by a colorful tile-covered dome and displaying Santa Fe's blue "cross" emblem on all four sides.

The grand interior space of the depot features natural redwood beam ceilings, highlighted by walls covered with a brightly colored ceramic tile wainscot.

Elaborate Hispano-Moorish designs are executed in green, yellow, blue, white, and black and the bottom and top edges are finished with a frieze of stylized ziggurats.