Canyon du Verdon is a spectacular canyon that forms a border between the Alpes-de-Haute-Provence and the Var. Up to 2,296 feet deep, the 13 mile long canyon varies in width between 19 and 328 feet at the bottom and 650 to 4,900 feet at its rim. The canyon was formed in the Quaternary Era, as a result of earth movements while the Alps were "growing" upwards and from erosion of the Jurassic limestone by the Verdon river. They remained unexplored until the 20th century.