Dubbed "Unbundling Wylerfeld," the project will improve connections and punctuality for regional and long-distance services travelling in and out of Bern, and is due for completion in 2022.

The project calls for the construction of a 300m tunnel for trains to Thun under the existing three tracks, which will allow for far greater flexibility in route planning. Two road bridges over the lines will be demolished and rebuilt to provide a wider span, and the station at Berne Wankdorf will be expanded.

Preparation work for the project began in January. It is part of a Swiss programme for the future development of railway infrastructure (ZEB), and is being financed through the ZEB programme, the infrastructure fund, the canton of Berne and the service agreement between the Swiss government and SBB.

Bern bottleneck map