Switching Montana City The crew of Montana Rail Link GP9 No. 109 and SD40-2XR No. 262 make quick work of switching the Ash Grove Cement plant at Montana City, Montana, on the afternoon of July 1, 2018. This 4.86-mile line from East Helena is all that remains of Great Northern’s Montana Central line from Helena to Butte, currently MRL’s 13th Subdivision and operated by the “Helena Switch” as-needed.