Maine Central 557 is an RS-3 1600 HP Diesel road switcher, built by Alco, October 1953 (construction #80567, sales order 20907, works order S-3219, shipped 11/53). One of two RS-3 units built for Maine Central (556 and 557), this locomotive is similar to NH 529 and Amtrak 140. It was originally equipped with a steam generator for heating passenger trains. Sold in 1976 to the (now defunct) Wolfeboro Railroad in New Hampshire, 557 passed through a number of owners while remaining in the same area of the state, finally being sold to the RMNE in March 1995. It was moved to Naugatuck Railroad’s Chase Yard in Waterville in November 1996.