This abandoned railway line opened in 1872, as the Lake Shore & Michigan Southern's (LS&MS) Franklin Division, running from Ashtabula to Andover, passing trough the towns of Jefferson and Dorset. It was connected to the Jamestown & Franklin Railroad at Andover, itself built in 1871, which provided connections to the coal and oil fields in western PA. At some point, the LS&MS leased the Mahoning Coal Railroad (built in 1873), which provided connections to coal fields of western PA to the steel mills in Pittsburgh, PA and Youngstown, OH.
A low-grade line was constructed in 1903 between Plymouth (now Carson) and Brookfield, OH, which eliminated the routing of slow-moving ore trains on the original, higher-grade line. The low-grade line was also straighter. After the opening of the low-grade line, the high-grade line became strictly a passenger route. By 1913, the LS&MS officially became part of the New York Central System (NYC), though the NYC had used the LS&MS for many years prior. Between 1922-1923, the high grade line was upgraded with heavier rail for 60 MPH operations, which enabled faster connections to and from the mainline.
By 1957, the struggling NYC ended passenger service in Jefferson, and concurrently removed trackage from Jefferson to Dorset. The NYC merged with the Pennsylvania Railroad in 1968, to become the ill-fated Penn Central (PC). In the early 1970s, the PC abandoned the portion of the high-grade line from Andover and Brookfield. By 1976, the bankrupt PC merged with several other bankrupt railroads to become Conrail.
In 1983, Conrail announced its intentions to abandon the portion of the high-grade line from Jefferson to Carson. However, in 1984, the State of Ohio purchased the segment, and in turn, leased it to a short-line railroad that still operates today, the Ashtabula, Carson, & Jefferson Railroad. In 1988, Conrail abandoned the remaining line east of Dorset. Today, the low-grade line is still in use by Norfolk Southern. The rest of the ROW remains undeveloped.
For an extensive history of this line, see The NYC's Franklin Division.
Thanks to Aaron M. for contributing information about this route.