The East Bay Electric Lines were a unit of the Southern Pacific Railroad that operated electric interurban-type trains in the East Bay region of the San Francisco Bay Area. Beginning in 1862, the SP and its predecessors operated local steam-drawn ferry-train passenger service in the East Bay on an expanding system of lines, but in 1902 the Key System started a competing system of electric lines and ferries. The SP then drew up plans to expand and electrify its system of lines and this new service began in 1911. The trains served the cities of Berkeley, Albany, Emeryville, Oakland, Alameda, and San Leandro transporting commuters to and from the large Oakland Pier (the "mole") and SP Alameda Pier. A fleet of ferry boats ran between these piers and the docks of the Ferry Building on the San Francisco Embarcadero. The East Bay Electric Lines became the Interurban Electric Railway (IER) in anticipation of the opening of the Bay Bridge Railway in January of 1939. This railway consisted of two tracks on the southern side of the lower deck of the San Francisco–Oakland Bay Bridge, running from the East Bay to the San Francisco Transbay Terminal. SP IER transbay commuter train service ended in July 1941. History Before Electrification (1863–1911) Prior to the formation of the East Bay Electric Lines (and later Interurban Electric Railway), commuter services by the Southern Pacific Railroad and predecessor Central Pacific Railroad were run entirely by steam traction. The first railroad to operate suburban services in the East Bay was the San Francisco & Alameda Railroad, which was formed on March 25, 1863. Through a series of mergers with the San Francisco, Alameda, & Stockton Railroad Company and the prior San Francisco & Alameda Railroad, the San Francisco, Oakland, & Alameda Railroad (SFO&A) was formed in June of 1871. The SFO&A would be absorbed by the Central Pacific Railroad in August. With the merger with the Central Pacific, trains would terminate at the Oakland Mole (a long ferry pier into the San Francisco Bay), starting in January of 1882. Suburban commuter services by the Central Pacific would be operated in the same manner after Southern Pacific took over. In 1902 the San Francisco, Oakland, & San Jose Railway (SFO&SJ) would build a three and a quarter long mile pier from Emeryville into the San Francisco Bay. The "Key Mole" as referred to by patrons would rival