The Lac de Serre-Ponçon, known in English as the Lake of Serre-Ponçon, is a reservoir on the border between the Hautes-Alpes and Alpes-de-Haute-Provence departments, in the Provence-Alpes-Côte d'Azur region, Southeastern France, one of the largest in Western Europe. The lake gathers the waters of the Durance and the Ubaye rivers, flowing down through the Hautes-Alpes and the Alpes du Sud to the Rhône. The waters are dammed by the Barrage de Serre-Ponçon, a 123-metre (404 ft) high earth core dam.

Hautes-Alpes is a department in the Provence-Alpes-Côte d'Azur region of Southeastern France. It is located in the heart of the French Alps, after which it is named. Hautes-Alpes had a population of 141,220 as of 2019, which makes it the third least populated French department. Its prefecture is Gap; its sole subprefecture is Briançon. Its INSEE and postal code is 05.