The line was opened by
Kristiania Sporveisselskab in 1875 as a
horsecar route between Stortorvet and Gamlebyen. In 1900 the line was electrified, and received branch lines to Kampen and Vålerenga. The Vålerenga Line was extended to Etterstad in 1923, where there was a transfer to the
Østensjø Line. Until 1925, the line was named the
Oslo Line; with the name change of the city from Kristiania to Oslo, the district known as Oslo was renamed Gamlebyen. The plans from 1919 called for a common connection from the Østensjø Line and the Ekeberg Line to the city center, along with the proposed Lambertseter Line. The Ekberg Line was to run through a tunnel from
Sjømannskolen to
Lodalen, from there over a bridge and then connect with the Østensjø Line at Harald Hårdrådes plass. They would then run along an elevated line along Schweigaards gate to
Vaterland, and from there in a tunnel to a terminus at
Stortorvet. In 1937, Ekebergbanen proposed a line south of Oslo gate on a bridge over Kongsveien, Oslo gate and the railway tracks, and then along Kanslergata to the proposed elevated line in Hollendergata. A formal concession was sent in 1937, but the plans were stopped by the war. After the war, it was decided that the Lambertseter Line would run from Bryn on the Østensjø Line, which would allow the Lambertseter Line, which had been proposed to connect to the Ekeberg Line, to become part of the metro. This terminated plans for rebuild the downtown section of the Ekeberg Line. There are plans to move the line from Schewigaards gate and let the line run through Dronning Eufemias gate as part of the development in
Bjørvika. The move was expected to be done in 2014, but finished in October 2020. ==References==