Pajares Rail Tunnel Opens!

Thursday, November 30th, 2023

The highly anticipated Spanish High Speed Rail Line, connecting Madrid and Asturias is now open, with the first service departing yesterday, shaving more than an hour off previous travel times. 

It is the first time that the service will connect directly to Asturias, utilising the newly opened Pajares Rail Tunnel with a length of 25.7km, one of the longest tunnels in the world. Dr. Sauer & Partners has played its role in both the design and construction of this monumental project which encompassed twin 10m diameter TBM hard rock tunnels, bifurcation chambers, cross passages, and emergency stops. The tunnel is lined with a pre-cast high-strength segmental lining with a thickness of 50 to 60cm. The connection between the access tunnel and the main tunnel required the construction of a large-span bifurcation chamber and a short mined tunnel. The excavation and support design considered the TBM tunnel in service to allow for simultaneous TBM tunnel construction progress.  

Dr. Sauer & Partners is delighted to see the full service in operation, having provided the final design of the bifurcation cavern and delivered engineering support services during construction.

Completed Bifurcation Cavern

Train in the newly opened tunnel (courtesy