The 50-mile Oregon and Northwestern began life as the Malheur Rail road, proposed in the early 1920s by Fred Herrick to fulfill a condition to harvest timber in the Ochoco and Malheur National Forests. In anticipation of the new business, the UP extended its The Oregon Eastern Branch from Crane to Burns in 1924.
Little was accomplished on the Malheur Railroad until the Edward Hines Western Pine Company bought the property in 1928, renaming it the Oregon and Northwestern Railroad. The O&NW was constructed in 1928-1929 between Burns and Seneca, where a mill and network of logging railroads were soon built. A succession of secondhand Consolidation and Mikado steam locomotives kept the line running until 1955, wher Baldwin's AS-616 diesel demonstrator No. 1600 arrived. Two Alco S-3 were purchased in 1956, but were replaced by three more Baldwn AS-616s acquired from the SP and McCloud River Railroad in 1966 and 1970, giving the O&NW the distinction of being an all-Baldwin enterprise.
Operations to Seneca dwindled to one train per week in later years. The March 6, 1984 train proved to be the last one before the Malheur Lake flood shut down UP's Oregon Eastern Branch, O&NW's only connection to true outside world. The flood washed out whole sections of track and collapsed the already shaky bridges. This proved to be the final straw for the line as it was already becoming uneconomical.
Since then, the planing mill in Seneca has moved to John Day, and the Hines Lumber Company sold its holdings (including the O&NW) to the Snow Mountain Pine Company, which after only a few brief years, shut down for good. All that exists of the mill is a muddy field.
When the Oregon Eastern Branch reopened, all but a few miles of the O&NW was abandoned. Its only connection, Union Pacific, abandoned its Oregon Eastern Branch in 1990 and removed the rails and ties in the spring of 1996.
The line is still very well preserved. The grade can be easily tracked as it cuts a path across the vast sagebrush flats of eastern Oregon. An interesting note is that near Crane, there still is a tunnel along the highway that is clearly visible and has no barrier blocking it at all. Up in the woods near Seneca, one can easily ride a bike on the grade as it passes through the stunning Trout Creek valley. It almost looks like a maintained gravel road, though it is for non-motorized use only. Numerous logging spur also existed along the line, though for lack of grading and ballast, most are gone now. Perhaps the most notable logging line was the Edward Hines Lumber Company line from Seneca to the northeast up to Summit Prairie.