Istres is a commune in southern France, some 60 km northwest of Marseille. It is in the Provence-Alpes-Côte d'Azur region, in the Bouc…Istres is a commune in southern France, some 60 km northwest of Marseille. It is in the Provence-Alpes-Côte d'Azur region, in the Bouches-du-Rhône department, of which it is a subprefecture. Istres is adjacent to the Étang de Berre lagoon and the Étang de l'Olivier lagoon. It is located some 60 km north-west of Marseille, 20 km south-west of Salon-de-Provence, 10 km north of Martigues and 45 km south-east of Arles. Istres is also adjacent to the plaine de la Crau and the Camargue national park.