Kolsåsbanen

Kolsåsbanen, known as the Kolsås Line, is a line of the Oslo Metro (T-bane) in Norway. It historically connected central Oslo with the western suburban town of Kolsås in the municipality of Bærum. The line runs from the city center into the western suburbs and is part of Oslo’s urban rail network that serves both dense urban areas and outlying neighborhoods.

The line began its life as an early 20th-century suburban tram or light-rail corridor and was gradually electrified and integrated into the city’s rail system. Over the decades it was upgraded and reorganized to function as part of the heavy-rail Oslo Metro. In the 2000s the Kolsåsbanen underwent a major modernization to align with the rest of the metro network, with stations, signaling, and rolling stock updated to meet metro standards. This modernization enhanced accessibility and service reliability along the western corridor.

Today, Kolsåsbanen operates as part of the Oslo Metro, providing a high-capacity connection from central Oslo to the western suburbs and the town of Kolsås. Trains on this line share track and operations with other metro services in central Oslo before diverging toward the western end of the route. The line is operated under the public transport authority framework for Oslo and Viken by the local transit operator in coordination with Ruter, Oslo’s public transport planner.

Kolsåsbanen serves as a key transit artery for commuters and residents in the western part of the Oslo metropolitan area, linking residential areas with the urban core and facilitating regional mobility.