Norges Statsbaner (NSB) operates three Y1 diesel railcars between Notodden and Porsgrunn each hour. The route is on contract with the county through the transit authority Vestviken Kollektivtrafikk. NSB uses diesel traction despite the railway being electrified.
History
Background
The need for a railway line from Notodden to Skien was driven forward by two key circumstances; the need for a railway to replace the Telemark Canal, and the construction of Sørlandsbanen.