SP had built to Tres Pinos by 1873, however they abandoned efforts to continue the line to Coalinga, instead choosing a more inland route from Lathrop.

[2] SP halted southward work at Soledad for thirteen years and started building north from Los Angeles in 1873, completing a line to Burbank.

[6] The first version of the Coast Line was completed by the Southern Pacific Railroad on December 31, 1900 when a train was run over the bridge at Cementerio, west of Goleta.

[2][9][b] The work between Ventura and Carpenteria eventually allowed the construction of the Rincon sea-level road for automobile traffic to travel this formerly impassible section of coastline.

In 1992, Southern Pacific granted the Los Angeles County Transportation Commission an option to purchase the entire Coast Line for passenger train operations at 110 mi/h (180 km/h).

[16] In the case of both purchases, SP retained freight trackage rights along those lines which continue to be held by the company's successor, Union Pacific.

[18] Freight trains were serving San Francisco via Caltrain tracks and Union Pacific's spur between Oakdale Avenue and Cargo Way as of 2007[update].

Ventura County would get rail curve realignments near Seacliff, the Santa Clara River and Montalvo in the near term for an estimated $300 million.

While a portion of the line was abandoned after being washed out in Los Angeles County, the Great Park development will provide for a route through the community of Valencia.