The Le Mans disaster (death toll: 84 lives) on 11 June 1955 brought the project to a halt. All race events were postponed. No further events were allowed to take place on temporary urban tracks. Racing events were only to be allowed on dedicated race-tracks, providing that they met a new set of rules. In Clermont-Ferrand, as was the case for many other new race tracks, new safety devices were being imagined and discussed, reviewed and assessed. But the concept of a "mountain race track" moved forward. It would be the only one of its kind in France.