The SF Belt started out at the Sate Belt Railroad, and then became the San Francisco Belt when the city acquired the port from the state. Although the railroad officially gave up the ghost in 1993, it never quite died. The remaining locomotives, two Alco S-2 switchers, were placed in the care of the Golden Gate Railroad Museum. In recent years, a new operator began business out of Pier 96 and required motive power. The two engines, still on the city's books, were leased to the new operator (LB Railco, now San Francisco Bay Railroad) and the San Francisco Belt Railroad resumed operations. Today, the two Alcos run on biodiesel and operate several times a week kicking cars around their yard and a couple of nearby industrial spurs.