From the salt mines used to launch the city into economic ... The solution was to build an underground tunnel to direct all ...

The chosen location was a salt mine in Austria, which the Nazis tried ... A mega project is underway in Denmark to build a tunnel under the Baltic to provide a link to Germany.

Runners will aim to complete 90 laps of the tunnel network, including some 65ft (20m) long sections that taller entrants are ...

Mine manager Doug Doney checks on machinery ... Kilometres of conveyor belts had to be built to move the salt along. In one tunnel, or stope, mining machine operator Jeff Lackie described ...

The race was the brainchild of Sussex Trail Events, whose members were inspired by Germany's Kristallmarathon, held in a disused salt mine. Runners will aim to complete 90 laps of the tunnel ...