Rhaetian Railway (RhB), the Federal Roads Office and the canton of Graubünden will rebuild the Fideris–Küblis corridor in Switzerland’s Prättigau valley, where the railway and N28 road currently share a narrow valley floor.
The core change is not only the Fideris Tunnel. The project removes the RhB line from the valley floor so the N28 can be straightened and separated from local traffic. Today, the road and railway run next to each other between Fideris and Küblis, with tight curves, lower speeds and exposure to flooding and mudslides.
For rail, the new alignment includes the 1,377-metre single-track Fideris Tunnel, new bridge structures and a connection to the existing double-track section before Küblis. RhB trains are currently limited to 45 km/h on this section; the new infrastructure will allow speeds of up to 120 km/h and reduce journey times by more than two minutes.
For road traffic, the project creates a separated N28 national road alignment and a local road. The N28 will be designed for 80 km/h operation throughout the section, while local traffic will no longer mix with through traffic. The local road will also provide an alternative route during maintenance or incidents on the national road.
The project includes seven new or replacement rail and road bridges, including the future Äuli Bridge at the eastern end of the Fideris Tunnel. One protected bridge will be renovated. The new structures are designed to meet flood protection requirements.
Fideris station will close in 2030 because of the construction works. The listed station building will be relocated and preserved.
Of the total EUR 498m (CHF 467.5m) budget, EUR 318m (CHF 298.5m) is allocated to rail infrastructure and EUR 180m (CHF 169m) to road infrastructure. Preliminary works are planned for 2028, main tunnel excavation for 2029–2032, commissioning of the railway tunnel for 2034, and completion of the N28 and local road for 2037.
