In 1915, a competition for a plan for the city's tramway light rails was launched, although it took two years for the invitation to be issued. In July 1918, the winner was announced, and in September 1919 a committee made a suggestion for how to expand the light rail network. It proposed connecting the Lilleaker Line to Majorstuen, a tunnel through the city center from Majorstuen to Stortorvet and Vaterland, and onwards as an elevated line eastwards, along routes that closely resemble the current metro lines and the Ekeberg Line. From Stortorvet, there was proposed a northern branch which would be built northwards towards Kjelsås. In addition, a route close to the current Ring Line was proposed.
