. 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 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 , which restricts speeds to . The tunnel was built between 14 May 2001 and August 2005. Gallery See also High-speed rail in Belgium References External links Belgian high-speed rail site High-speed railway lines in Belgium Railway lines opened in 2009 Standard gauge railways in Belgium