Trunk Line
Several routes were considered for the Loenga–Alnabru Line. The need to keep the gradient at bay meant that the tracks were placed at a lower elevation than the Trunk Line, with the two not reaching the same height until Bryn Station. At the same time the company needed to stay away from the Alna River. Meanwhile, the Gjøvik Line was built with a branch, the Alna Line, which connected to Alnabru. Just northeast of the Trunk Line was placed in a culvert under the Trunk Line so it would meet up with the Alna Line. The Loenga–Alnabru Line was completed between Bryn and Alnabru in May 1904. with this work being carried out at the same time as the doubling of the Trunk Line. The section from Loenga to Bryn opened on 1 May 1907.