Its main line from Vallejo to Sacramento was completed six months prior to the May 1869 golden spike ceremony of the Central Pacific/Union Pacific Transcontinental Railway.

Beginning January 1869, the company operated a passenger ferryboat (New World) from San Francisco to Vallejo and thence a railroad to Sacramento.

Amtrak's Capitol Corridor follows the original Cal-P Line from Sacramento to Suisun/Fairfield on its way to, via Martinez, Oakland and San Jose.

The first truly transcontinental railroad was completed September 1869, from Sacramento through Stockton, over Altamont Pass and thence via Niles Canyon to the San Francisco Bay Area, a distance of 120 miles (190 km).

The route over Altamont Pass was completed to Alameda Terminal in September 1869 (and to Oakland Long Wharf in November 1869).

Central Pacific announced plans to build a parallel route of the Cal-P but diverging at Napa Junction via the Suisun Marsh to Benicia.

That same month the Company entered into contract with Dewitt Clinton Haskin to build the entire railroad.

[7] The California Pacific commenced construction at South Vallejo (west of the Carquinez Bridge) in December 1866 under the contractor D. C. Haskin.

Two months after tracklaying began, the track was completed from Vallejo, via Napa Junction and Jameson Pass, to Suisun on June 24, 1868.

[12] The line from Davis to Woodland was later operated by the Southern Pacific and currently by the California Northern Railroad.