The story begins in the 1880s with the mines at Kiruna and Malmberget in Swedish Lapland. LKAB's predecessor, Gellivare Aktiebolag, received a mining concession in 1884 and completed the first section of the Ore Line from Malmberget to the Baltic port of Luleå in 1888. But Luleå freezes. The company went bankrupt in 1889, and the Swedish government bought the line for eight million kroner, half of what it had cost. The solution to the ice problem lay across the border, where the Ofotfjorden stayed open year-round thanks to the warm currents of the Gulf Stream. Construction of both the Ore Line extension and the Ofoten Line began in 1898. By 1902, ore was flowing from Kiruna through Riksgränsen and down to ships at the Port of Narvik.

The Ore Line was electrified between Riksgränsen and Kiruna on 19 January 1915. Plans for electrifying the Norwegian side had existed since 1911, but parliament delayed approval until 1920. Electric traction began on 15 May 1923, using borrowed Swedish locomotives until Norway's own El 3 and El 4 classes arrived in 1925. The El 3 was a twin-unit machine producing 2,132 kilowatts; the El 4 was longer, more powerful, and ran as a single unit. When war came in April 1940, the ore traffic stopped. The Battles of Narvik devastated the town and the railway. A bridge called Norddalsbron, built deliberately long so it could be demolished in wartime, was blown up, though insufficient explosives meant the Germans could repair it. Two El 4 locomotives were destroyed beyond recovery. The line was rebuilt, and by the postwar decades, heavier El 12 and El 15 locomotives took over the ore trains.

By the 1980s, LKAB wanted cheaper transport. Norwegian State Railways was making a 50-percent profit margin on ore haulage, roughly 60 to 70 million kroner annually. What followed was a decade-long struggle between LKAB, the state railways of Norway and Sweden, and the Norwegian government. In 1992, LKAB won Swedish traffic rights but was denied on the Norwegian side. The company tried EU regulations, subsidiary structures, and political pressure. In September 1992, three thousand people in Narvik staged a general strike against LKAB's plans. By 1995, a joint venture was finally agreed: LKAB would hold 51 percent, with NSB and SJ splitting the rest. The Norwegian Parliament voted 67 to 45 to approve it in June 1996. Malmtrafik, the new operator, took over on 1 July 1996, becoming the first private railway company in Europe to haul international freight trains.

Today the Ofoten Line carries more than ore. CargoNet runs two daily container trains branded the Arctic Rail Express, hauling food northbound and fish southbound on a 1,950-kilometer route from Oslo that takes 27 hours via Sweden. SJ operates passenger trains including a night service to Stockholm. Since 2020, the Arctic Train has offered summer excursions between Narvik and Bjornfjell for tourists and cruise ship passengers. But iron ore remains the spine of the operation. LKAB's port at Narvik handles up to 25 million tonnes per year. The line was upgraded to 30-tonne axle loads by 2003, and new Iore locomotives, ordered from Bombardier in 1998, can haul trains of 68 cars. The passing loops along the entire route from Narvik to Luleå were extended to 790 meters to accommodate the longer trains. What began as a single-purpose mining railway now carries the full weight of Arctic commerce.