The St. Paul and Duluth Railroad was reorganized from the Lake Superior and Mississippi Railroad in 1877. It was bought by the Northern Pacific in 1900. Known to this day as the "Skally Line", it operated from Saint Paul to Duluth, Minnesota, with branches to Minneapolis, Taylors Falls, Kettle River, and Cloquet, in Minnesota, and Grantsburg and Superior in Wisconsin.
The line was purchased by the Northern Pacific Railway, which was succeeded by the Burlington Northern and then the Burlington Northern Santa Fe. Most of the line became redundant with other lines after the Burlington Northern merger, as it paralleled another line of the Great Northern Railway. Most of the line therefore was abandoned and many segments were turned into rail trails.
The disposition of those segments is as follows: