Run by Flytoget AS (formerly NSB Gardermobanen AS), it operates on the high-speed Gardermoen Line using sixteen GMB Class 71 electric trains.

Construction started in 1994 and high-speed trains began serving Gardermoen Airport from the date of its opening on 8 October 1998, although full operation using the 14.5-kilometre-long (9.0 mi) Romerike Tunnel had to wait another ten and a half months after severe leaks caused by the tunnel's construction led to the partial depletion of two lakes.

But no operation speeds exceeding 160 kilometres per hour (99 mph) are achieved there due to short distances and limitations to rolling stock, making Gardermobanen the first real high-speed railway line in Norway.

[2] The greatest challenge was the need to build the 14,580-metre (47,830 ft) Romerike railway tunnel – Norway's longest – beneath the geologically highly unstable Østmarka area between Etterstad, close to Oslo Central Station, and Lillestrøm.

[6] During construction, in 1997, the water level in some lakes above the tunnel, including Lutvann and Nordre Puttjern, sank dramatically.

After the leaks were discovered on 3 February 1997, sanctions were imposed by the Norwegian Water Resources and Energy Directorate requiring the elimination of all leakages.

[9] Further complications arose due to conflicts between NSB Gardermobanen and the construction company, Scandinavian Rock Group, with the latter at one instance stopping work for three weeks while the parties quarrelled in court.

Construction of the tunnel caused damage to around sixty houses and an evaluation by the Ministry of Transport and Communications showed that NOK 500 million was spent on fixing the leaks and claimed that this was to a large extent an unnecessary expenditure which more efficient engineering procedures would have avoided.

[2] The first steps of organisational restructure were taken 29 June 2000, when the CEO of NSB, Osmund Ueland, was fired due to several incidents related to the operations of NSB—not just the Gardermo Line.

[12] The debt in NSB Gardermobanen had become unmanageable, and in April 2000 parliament accepted that it would not be possible to make the Gardermo Line—with the current structure—the profitable venture predicted in 1992.

From 1 January 2001, the company changed name to Flytoget AS, retaining ownership of the trains and operations and kept as a subsidiary of NSB.

[2] On 9 December 2002, parliament decided that Flytoget AS would become a separate railway company from 1 January 2003, owned directly by the Ministry of Transport and Communications.

[2] One year later the ownership was transferred to the Ministry of Trade and Industry as part of a cleanup of political overhaul between the departments.

[13] As part of the process, a new CEO, Thomas Havnegjerde, was appointed in June 2002,[14] and in January 2003 the new chair, Endre Skjørestad—who took over the position form NSB's director Einar Enger.

Reduced fares with 50% discount are offered to senior citizens, children, youth under 21 years, students, benefit recipients and military personnel.

[29] During the 2007 recruitment half of the newly educated train drivers chose Flytoget over Vy, mostly due to higher wages.

[32] Several other deaths on the line have been classified as suicides, and so are not in the accident statistics;[33][34] they do however cause delays on all services for hours after the incident takes place.

[42] But problems also incur on the new sections, regularly delaying service or capacity, and forcing Flytoget to operate fewer departures.

[48] When Al Gore came to Oslo to receive his Nobel Peace Prize on 7 December 2007, he used the Airport Express Train to make his journey as environmentally friendly as possible.

[49] The company has initiated a program to ensure better diet for the employees; this had made several lose weight and has reduced the level of sick leave from 12 to 8%.

[8] Among the features are pressure-tight cabins to allow comfortable travel through tunnels at high speeds, and step-free access to the cars.