Barrage de Malpasset, Piste d'Ambon, Fréjus, Draguignan, Var, Provence-Alpes-Côte d'Azur, France métropolitaine, 83603, FranceDépartement du Var
Wikipedia[1][3], the Fréjus Tourist Office and the European Rivers Network all date the collapse to 2 December 1959; the tourist office gives 21:13 as the time of failure.
The thin arch Malpasset Dam on the Reyran River collapsed on the night of 2 December 1959 after weeks of rain, flooding Fréjus on the French Riviera and killing 423 people.