On 2nd July 2026, Swiss state railway SBB officially started construction work on the multi-track expansion of the Zurich – Winterthur line. With a budget of around EUR 3.6 billion (CHF 3.3 billion), this marks the start of what the SBB describes as the company’s largest infrastructure project to date, which is intended to eliminate one of the most significant bottlenecks in the Swiss network and increase capacity in the corridor by around 30%. At the heart of the project is the 9 km Brütten Tunnel, which will create a new double-track line between Bassersdorf and Winterthur. Together with the expansion to four tracks in the Zurich – Winterthur corridor and works at the stations in Wallisellen, Dietlikon, Bassersdorf and Winterthur Töss, this will create additional capacity for long-distance passenger rail transport, the Zurich suburban rail (S-Bahn) network and rail freight transport. The construction period will last ten years. Tunnel boring will begin in 2029, and the Brütten Tunnel is scheduled to open in 2037. The station refurbishments will be phased in between 2028 and 2034. In the future, the corridor is expected to handle around 900 trains and more than 150,000 passengers daily.