The Coudersport and Port Allegany Railroad was a shortline railroad that operated in Potter and McKean Counties in Pennsylvania in the United States between 1882 and 1964. The original line ran 17 miles (27 km) along the Allegheny River between the boroughs of Coudersport, the county seat of Potter County, and Port Allegany in McKean County. The line was originally a 3 ft narrow gauge and converted to 4 ft 8+1⁄2 in standard gauge in 1889. It was prosperous during a lumber boom in the region and expanded east to Ulysses. The lumber boom ended in the early 20th century and the line slowly declined until 1964, when it was purchased by the Wellsville, Addison and Galeton Railroad. The line was finally abandoned in 1970. Today the only surviving building from the railroad is the Coudersport and Port Allegany Railroad Station, which was listed on the National Register of Historic Places in 1976 and serves as the town hall for Coudersport today. As of 2009, much of the C&PA railroad grading can still be found. Railroad bridge abutments exist at Lillibridge Creek in Port Allegany and along the Allegheny River at Coleman Mills, east of Roulette, and east and west of Coudersport.

The Wellsville, Addison & Galeton Railroad was formed in 1954 to operate a section of Baltimore & Ohio Railroad (B&O) trackage which had been isolated from the rest of the system by a 1942 flood. This trackage was acquired by the B&O as part of the purchase of the Buffalo & Susquehanna Railroad (B&S) in 1932. It is known as the operator of a set of GE centercab diesels supplemented by F7 locomotives in later years.