It is owned by the Norwegian National Rail Administration Vy operates three Class 69] EMUs between Notodden and Porsgrunn each hour.

From the opening in 1909 Rjukan Salpeterfrabrik had transported their ammonia for shipment from Skien along the Rjukan Line, the Tinnsjø railway ferry and the Tinnos Line to Notodden, where the ammonia was transferred from railway wagons to barges and shipped down 54 kilometres (34 mi) along the Telemark Canal to Skien.

At the time many locals wanted to expand the canal instead of building a railway—to allow ocean-going vessels to enter the port at Notodden and removing the need for transshipment in Skien.

Plans were launched by Sigurd Kloumann in 1911, but rejected by the management of Norsk Hydro who preferred a continual railway line.

Budget exceeding would be covered by new shares sold to the state, and the company would build up a fund for the later expropriation of the line.

An agreement with Norsk Transport was made on 4 October 1913, which dictated that the Tinnos Line was transferred to the state from 1 July earlier the same year.

The passenger and general cargo transport on the line was not profitable, and Norsk Hydro had to subsidize this through higher fees on their freight.

During the first half of the 1930s the price of potassium nitrate fell 60%, and in 1934 Norsk Hydro announced they would move production; to compensate the state agreed to in part subsidize the transport on the railway.

[10] From the 1960s the production at Rjukan decreased steadily, and the plant was finally closed on 1 July 1991; the last freight train was run four days later.