Lake Superior and Ishpeming Railroad

The Lake Superior and Ishpeming Railway was organized in 1893 as a subsidiary of Cleveland-Cliffs Iron Company (now Cleveland-Cliffs Inc.), the iron ore mining company. From the start the railroad's primary business was the transport of iron ore from the Marquette Iron Range, west of Marquette, to docks on Lake Superior from which the ore could be shipped to steel mills on the lower Great Lakes. The primary towns on the iron range are Ishpeming and Negaunee, Michigan.In 1904 the railroad carried over 1.2 million short tons (1.1 Mt) of freight, and over 1.1 million short tons (1.00 Mt) of that was iron ore. It had 489 ore cars, 14 locomotives, and 121 employees.

In 1923 the LS&I Railway merged with the Munising, Marquette and Southeastern Railway (MM&SE), a short line running from Marquette 40 miles (64 km) east to Munising to form the LS&I Railroad. The LS&I's new spur ran through a section of the Upper Peninsula thickly forested with pulpwood, adding a second commodity to the LS&I's workload. The MM&SE/LS&I also operated a second spur from Marquette northwest to Big Bay.

Passenger operations were never major. In 1904 the railroad carried over 180,000 passenger-miles, compared to over 24 million ton-miles (35 million tkm) of freight. In 1931 two trains a day ran each way from Munising to Lawson, Marquette and Princeton. One train ran from Marquette to Big Bay and one on the east branch from Munising to Shingleton. By 1940 the Munising-to-Princeton and Lawton-to-Marquette service had been reduced to one train a day each way, and Big Bay service was operating three times a week. This level of service lasted at least to 1950. By 1955 the only passenger service remaining was a single daily train from Munising to Princeton; Marquette and Big Bay were no longer served. All passenger service had been discontinued by 1960. By 1962, diesel locomotives had replaced steam locomotives on the line.

The Big Bay spur was sold in the 1960s and Munising operations ended in the 1980s. A line between Humboldt and the Republic Mine (part of the Marquette Iron Range) was abandoned and railbanked in 2004. Part of the line was reactivated by the Mineral Range Railroad in 2012 for a new mine, the Humboldt Mine.

As of 2016, the Lake Superior & Ishpeming's primary remaining business continued to be the transport of iron ore over a 16-mile (26 km) short line from the Tilden Mine south of Ishpeming, operated by Cleveland-Cliffs, to Lake Superior for transport. Tonnage was declining sharply due to the shutdown of the adjacent Empire Mine, also historically served by the LS&I.