The Upland–San Bernardino Line was an interurban line operated by the Pacific Electric Railway between Downtown Los Angeles and San Bernardino, California. This line also had shorter service that terminated before the end of the line at Baldwin Park, Covina, and San Dimas. Though service along this line in its entirety was discontinued in November 1941, it stands as the fourth-longest rapid transit line in American history, after the Sacramento Northern and services, and the Pacific Electric's own Riverside–Rialto Line.