Soumagne Tunnel

The Soumagne Tunnel is the longest rail tunnel in Belgium, with a length of 6505 m. Built on the HSL 3 line of the Belgian TGV service for Brussels-Liège-Cologne, the tunnel was completed in 2004. The new line was opened on June 12, 2009. The tunnel links the Liège conurbation with the Herve plateau at a depth of 120 m. Construction and outfitting of the tunnel took place from 2001 to 2005, with the first trains passing through in 2009. The entrances are at and Soumagne. The tunnel passes under Chaudfontaine, Fléron, and.

The bored section is 5940 m, extended by covered sections of respectively 177 and 388 m. Dozens of geological layers of differing hardness had to be tunnelled through, lime layers needing to be blasted through with dynamite. The tunnel reaches a depth of 127 m in some areas; it has an average ramp height of 1.7%, with a maximum of 2% at the entrance in Soumagne. The free space profile in the tunnel is approximately 69 m2, which restricts speeds to 200 km/h.