In the middle of the night a mass on the north side of Mont Granier suddenly collapsed, in one of the largest historical rockslope failures known in Europe.

Mont Granier (1,933m) is a limestone mountain located between the départements of Savoie and Isère in France. It lies in the Chartreuse Mountains range of the French Prealps between the towns of Chapareillan and Entremont-le-Vieux. Its east face overlooks the valley of Grésivaudan and Combe de Savoie, and the north face overlooks Chambéry. At 900 meters tall, Mont Granier has one of the highest cliffs in France.