NYO&W Engine No. 49
(was No. 78 2-6-0 Rebuilt)
Builder: Rd. Isl.  1872
Wheel Configuration:  0-6-0
Location: New York

The New York, Ontario and Western Railway, more commonly known as the O&W or NYO&W, was a regional railroad with origins in 1868, lasting until March 29, 1957 when it was ordered liquidated by a US bankruptcy judge. The O&W holds the distinction of being the first major U.S. railroad to be abandoned in its entirety.

The railroad began life as the New York and Oswego Midland Railroad, organized by Dewitt C. Littlejohn in 1868. Its mainline ran from Weehawken, New Jersey in the greater New York City area to Oswego, New York, a port city on Lake Ontario. It had branch lines to Scranton, Pennsylvania; Kingston, New York; Port Jervis, New York; Delhi, New York; Utica, New York and Rome, New York. The part south of Cornwall, New York was operated over the New York Central Railroad's West Shore Railroad via trackage rights.