Passengers on this symbolic first run included German transport minister Dr Peter Ramsauer, German Rail (DB) CEO Dr Rüdiger Grube and Baden-Württemberg state transport minister Mr Winfried Hermann. The 9.4km tunnel, which is Germany's third-longest, took nine years to construct and is part of a 17.6km stretch being upgraded at a cost of €610m, financed by the German federal government, the European Union, and DB.

"The opening of the Katzenberg tunnel represents an important milestone in the upgrading of the railway line between Karlsruhe and Basle," says Grube. "It not only brings urgently needed new capacity for passenger and freight transport on this main European line, but also reduces noise pollution for residents in this part of the Rhine valley."

The tunnel is part is a €5.7bn project to upgrade the 182km Karlsruhe – Basle line to four tracks.