The line was constructed as the Santa Cruz Railroad between 1873–1876 and was laid with narrow gauge rail. Sold to Southern Pacific after foreclosure, converted the line to standard gauge and operated until the actual merger into Southern Pacific on 14 May 1888. The Aptos branch from Aptos to Loma Prieta was built as the Loma Prieta Railroad in 1883 and abandoned in 1928. The line was extended to Davenport in 1905. Until 1940, the line connected in Santa Cruz with the former South Pacific Coast Railroad to San Jose, California as an alternative Southern Pacific Coast Line route north of Watsonville Junction. A cement kiln in Davenport provided one hundred carloads weekly of inbound coal and outbound cement. Inbound lumber and outbound refrigerator cars of locally grown Brussels sprouts, artichokes, and lettuce provided additional freight traffic. Suntan Special summer excursion trains carried 900 passengers per trip from San Francisco to the Santa Cruz Beach Boardwalk from July 1947 to September 1959. There was a railway turntable and 5-stall roundhouse in Santa Cruz, but steam locomotives were replaced by EMD GP9s in 1955. Daily local freight service was replaced in 1982 by tri-weekly branch line trains operating at per hour including a caboose until 1986. The Pajaro River bridge was damaged by the 1989 Loma Prieta earthquake. The line came under ownership of Union Pacific in 1996. As of 2012 the corridor is owned by the Santa Cruz County Regional Transportation Commission. At that time freight operations were contracted out to Iowa Pacific Holdings, commencing service in November 2012. In 2018, Progressive Rail, Inc. was chosen as the replacement freight operator under a 10-year contract.
Route
The right of way begins in Watsonville Junction, where it interchanges with Union Pacific's Coast Line. The line features street running sections in Watsonville and Santa Cruz where trains interact directly with roadway traffic. The Santa Cruz, Big Trees and Pacific Railway operates part of its heritage railway service along SCMB tracks from the Santa Cruz Beach Boardwalk to that railroad's main line east of the Beach Street roundabout, before turning onto its own tracks at the Santa Cruz Wye towards Felton on the former South Pacific Coast Railroad mainline. After leaving Santa Cruz, the line runs parallel to Highway 1 until Davenport, where the tracks end suddenly.
