The West Coast Line is one of the most important railways in Sweden. Its expansion to a double-track railway has been under way for many years and currently approximately 85 per cent of the West Coast line has been upgraded. With a fully upgraded double track, the capacity of the line will be greater and will mean an increase in the frequency of services for both passenger and freight trains.

This upgrading to double tracks will increase the technical standard of the entire West Coast Line. This means that speed can be increased, which reduces travelling time and also provides greater reliability.