The San Diegan was one of the named passenger trains of the Atchison, Topeka and Santa Fe Railway, and a “workhorse” of the railroad.

Construction of the Surf Line between Los Angeles and San Diego began on October 12, 1880, with the organization of the California Southern Railroad Company.

On January 2, 1882, the California Southern commenced passenger and freight service between National City and Fallbrook Junction, just north of Oceanside.

[1] The Santa Fe assumed control of the California Southern and on August 12, 1888, completed the line between Los Angeles and San Diego.

A second San Diegan consist entered service on June 8, 1941, doubling the schedule to four daily round trips.

The Daylight/Starlight was cut back to Los Angeles in April, and Amtrak restored the third San Diegan round trip to maintain the same level of service along the corridor[17] Beginning in 1976 the state of California funded additional service: a fourth round-trip on September 1, 1976, a fifth on April 24, 1977, a sixth on February 14, 1978, and a seventh on October 26, 1980.

[21] Motive power consisted of a single 1,800 hp (1,300 kW) EMC E1A locomotive sporting the familiar Warbonnet paint scheme.

Santa Fe's lone trio of Fairbanks-Morse (FM) "Erie-built" locomotives and the odd GE U28CG could also be seen occasionally running the line.

[citation needed] The San Diegan also enjoyed almost exclusive use of Santa Fe's "pendulum-suspension" chair car, No.

[25] For a six-month period in 1978 service on the route was supplemented by the El Camino cars owned by Los Angeles County.