 Despite the older line being double track, capacity had reached its limit due to a combination of some trains making many stops and others none until Lillestrøm.The Romerike Tunnel would also be straighter and allow higher through speeds, decreasing travel time from 29 to 12 minutes.The decision to build the Gardermoen Line and Romerike Tunnel was taken by the Norwegian Parliament on 8 October 1992, with the opening planned for six years later on 8 October 1998.