The Homestake Pass Line, running from Garrison, MT to Logan, MT via Butte and Homestake Pass, was built in 1888 by the Northern Pacific Railway and owned by Burlington Northern starting in 1970. The Homestake Pass Line saw both passenger and freight traffic during its time in service. While not officially abandoned, the line has been inactive since 1983, and is currently owned by the BNSF Railway. Today, large portions of the line remain intact, although the rails are severed just east of Butte, MT and many road crossings have been paved over.
Thanks to Peter Lewis and Kevin M. Smith for contributing information about this route.