would build noise screens along the line. The city council voted in favor of building the Ring Line on 25 June 1997, against the votes of the Progress Party. Financing was partially ensured in December, when a political agreement was reached for Oslo Package 2, a financing plan for investments in public transport in Oslo and Akershus between 2002 and 2011. Construction started in June, with the Agency for Road and Transport of the municipality responsible for construction. The first section opened from Ullevål stadion via Nydalen to Storo on 20 August 2003. With the opening, Line 4 was extended from Ullevål stadion to Storo. On 20 August 2006, the final section opened, from Storo via Sinsen to Carl Berners plass. In 2002, the Sognsvann Line was closed during the summer vacations due to improvements of the track and third rail. In 2008, the line was closed for approximately one week, due to leaves that had covered the tracks. The operation of the line was replaced by buses that served temporary stops in Nordbergveien and Sognsveien. In 2010, a truck was stuck under the train bridge between Holstein and Kringsjå over Carl Kjeldsens vei. The bridge was damaged, and allowed for only one-way-traffic for two weeks. Half the trains had to stop at Berg in the meantime. Route The line branches off from the Common Tunnel after Majorstuen, and heads northwards through the borough of Nordre Aker. The first two stations, Blindern and Forskningsparken, serve the Blindern campus of the University of Oslo. At Forskningsparken, there is transfer to the Ullevål Hageby Line of the Oslo Tramway, which allows connection with the two largest hospitals in the country: Rikshospitalet and Ullevål University Hospital. Ullevål stadion serves Norway's largest sports venue, Ullevål Stadion, the home ground of Norwegian Premier League side Vålerenga and the national football team. North of Ullevål stadion, just before reaching Berg, the Ring Line with services 3 and 4 branches off. The Ring Line serves three stations, Nydalen, Storo and Sinsen before reaching the Grorud Line. From Berg to Tåsen, the line runs parallel to the motorway Ring 3. North of Berg, the Sognsvann Line mainly serves residential areas, including student dormitories at Sogn and Kringsjå. The Norwegian School of Sport Sciences and the National Archival Services of Norway is served by Sognsvann Station. The station also serves the recreational area Nordmarka and the lake Sognsvann. Service