Welcome to a historic breakthrough. Freight traffic on this route was predominate already in the 19th century. Ore, timber, peat, charcoal and explosives were transported, among other things. The railway became an artery which created jobs in the areas between Nora and Otterbäcken. The railway from Nora to Otterbäcken was completed and put into operation in 1876. The corporation operated railway traffic with its own vehicles and rail, a total of 173 km on the sections Bredsjö - Gyttorp - Karlskoga - Otterbäcken and Gyttorp - Nora - Ervalla. The business was dominated by freight transport with iron ore from the area's mines to the port of Otterbäcken.

Passenger traffic was operated by passenger carriages in cargo trains and rail buses. It ended during 1966 in favor to road trafficked busses, which NBJ also operated. The rail buses was operated twice a day between Nora and Otterbäcken. When the mines in Bergslagen were closed down towards the end of the 1960s, the income from the ore transports ended. In the mid-1970s, NBJ began to be wound up and in 1979 the remaining parts of SJ were taken over. The Gyttorp - Bredsjö line was liquidated in 1979, but there is plenty of railway history left along the line.

On the southernmost part of Strömtorp - Otterbäcken, cargo traffic continued until 1994. The section Gullspång - Otterbäcken was liquidated during 2002. But the Strömtorp - Gullspång section remains and here you can step on the trolley on the Trelänsbanan. Today, commercial traffic is only operated for 22 kilometers on the former NBJ line, more exactly between Strömtorp and Bofors. On the section Ervalla - Nora - Gyttorp - Karlskoga, Nora Bergslags Veteran-Jernväg a museum kind traffic is running.

During 1960s the competition from car traffic became pretty noticeable for railways. In addition, the need of traffic ended when the mines began to close due to poor profitability. The last ore train operated in April 1974, five years after the mine in Striberg shut down its operations. The railway still continued to make a living from scrap and oil transport, but in 1976 the economy was so bad that the state had to take over the operations. As a state-owned company, the traffic survived for another nine years, but in 1985 the company NBJ was finally closed down and an almost 130-year era ended.