This railway was built by the Chicago and North Western Railroad and was completed in September of 1873. Its completion gave a direct route over the C&NW between Saint Paul and Chicago, IL. It was abandoned by the C&NW in 1965.
The line is well-known locally for a couple of reasons. First, it not only has three tunnels on its route, but each tunnel was dug by hand. Second, the portion of the grade between Sparta and Elroy hosts the Sparta-Elroy Rail-trail, long considered to be the first instance of an abandoned railroad grade that was converted to pedestrian/bicycle use in the nation, and thus the original rail-trail; it remains a popular trail today. The remainder of the line, between Elroy and Reedsburg, also serves as the 400 Rail-trail.