Oslo Airport, Fornebu opened in 1939, and from the 1980s the Norwegian State Railways (NSB) proposed serving it with a branch of the Drammen Line.
However, the zoning plans state that full-scale development of 6,000 residences and between 15,000 and 25,000 jobs cannot take place until a rail transit has been established.
After discarding proposals for a railway and a tram-train, Akershus County Municipality planned a people mover to Lysaker Station.
This was approved of in 2004, but in 2007, the county changed its opinion and instead opted for a connection to the Oslo Tramway, allowing direct access to the city center.
The project is estimated to cost 26.4 billion Norwegian krone and began construction in December 2020, aiming to finish in 2027 - it has since been delayed to 2029.
The ground transport system was a major part of the considerations and proposals were made both for motorway and railway access to all the alternatives.
[14] A series of weather surveys were then published which showed unfavorable conditions and the matter was again brought up for political consideration.
[16] NSB changed their scheduled so all InterCity Express and long-distance trains on the Drammen Line started stopping at Lysaker.
[17] Oslo Sporveier and the Norwegian National Rail Administration launched a proposal for a tram-train service in 1997, largely inspired by the Karlsruhe model.
[22] Both a 1992 and a 1997 report concluded that it would benefit society the most if Fornebu was redeveloped as a residential area, with as many as 14,000 residences being quoted as a suitable number.
[23] The mainline railway alternative was based on the Asker Line being routed via Fornebu instead of running directly to Lysaker from Sandvika Station.
[28] Akershus County Municipality issued a report investigating tramway, people mover and bus rapid transit in March 2002.
The county council voted in June to pursue a people mover, although it kept the possibility open for a connection onwards via tramway or metro.
Further reports were issued in December 2002 and February 2003, and in April 2003 the county again approved a people mover, and asked Oslo Municipality to build a metro line to Lysaker.
[26] A contributing factor was that a large array of expert bodies, including Oslo Sporveier, the Public Roads Administration, the Institute of Transport Economics and a series of consulting companies all recommended that a people mover was not suitable.
[31] It thereby concluded that a tramway would not be suitable and eventually landed on that a metro line exclusively in a tunnel via Skøyen to Majorstuen would be preferable.
It cited the need for quick travel speeds to the city center, connection with the other transit systems and sufficient capacity to handle increased development at Fornebu.
There is funding in Oslo Package 3, an amalgamation of various national and local grants and toll fees, but this is insufficient to finance construction, even if it is delayed until 2027.
[35] An alternative way to generate additional funding is that the land-owners pay for part of the infrastructure in exchange for a change to the zoning allowing more dense construction.
[36] The 1919 proposal for a light rail was based on the standard of the western suburban lines, which are today part of the metro.
The municipal committee saw the line not only as a possibility for serving local residents, but also to transport day tourists from the city to the seaside.
[37] The 1981 proposal by the Institute of Transport Economics called for a mainline railway service to Fornebu as a single-track branch from the Drammen Line to the airport terminal.
NSB preferred the loop, as it allowed trains running along the Drammen Line to deviate via Fornebu and serve the airport.
[54] A major advantage with the people mover was that it would allow for a good geographical coverage of the peninsula and could be built to make all bus services superfluous.
At the latter site it would instead connect to the Skøyen Line of the tramway via Bygdøy allé and run to the city center and Jernbanetorget.
This allows it to be built without interrupting operations at Lysaker Station, without interfering with the structures on the lot above and giving sufficient depth to pass under Lysakerelva.
The Norwegian Public Roads Administration is considering alternatives for handling increases buses, including that of building a bus terminal.
However, Ruter was concerned that it would be difficult to create an efficient system without large-scale bus lane conversion in the city center.
[72] A major challenge with the metro alternative is the network's congestion through the Common Tunnel, which is shared by all lines between Majorstuen and Tøyen.
Currently the capacity through the tunnel is limited to 28 trains per hour per direction, although Ruter hopes than improvements in signaling can increase this to 32.